Since [NUMBER] is broken, I decided to try out actually individually defining each of the body parts. Testing seems (to me) to indicate that the given body parts now work more like they were intended.
Just tossing it up here in case anyone else would like to do the same.
[BODY:TEETH]
[BP:F_U_R_INCISOR:first upper right incisor:STP][CONTYPE:HEAD][CATEGORY:TOOTH][SOCKET][SMALL]
[DEFAULT_RELSIZE:1]
[BP:F_U_L_INCISOR:first upper left incisor:STP][CONTYPE:HEAD][CATEGORY:TOOTH][SOCKET][SMALL]
[DEFAULT_RELSIZE:1]
[BP:S_U_R_INCISOR:second upper right incisor:STP][CONTYPE:HEAD][CATEGORY:TOOTH][SOCKET][SMALL]
[DEFAULT_RELSIZE:1]
[BP:S_U_L_INCISOR:second upper left incisor:STP][CONTYPE:HEAD][CATEGORY:TOOTH][SOCKET][SMALL]
[DEFAULT_RELSIZE:1]
[BP:R_E_TOOTH:right eye tooth:right eye teeth][CONTYPE:HEAD][CATEGORY:TOOTH][SOCKET][SMALL]
[DEFAULT_RELSIZE:1]
[BP:L_E_TOOTH:left eye tooth:left eye teeth][CONTYPE:HEAD][CATEGORY:TOOTH][SOCKET][SMALL]
[DEFAULT_RELSIZE:1]
[BP:F_L_R_INCISOR:first lower right incisor:STP][CONTYPE:HEAD][CATEGORY:TOOTH][SOCKET][SMALL]
[DEFAULT_RELSIZE:1]
[BP:F_L_L_INCISOR:first lower left incisor:STP][CONTYPE:HEAD][CATEGORY:TOOTH][SOCKET][SMALL]
[DEFAULT_RELSIZE:1]
[BP:S_L_R_INCISOR:second lower right incisor:STP][CONTYPE:HEAD][CATEGORY:TOOTH][SOCKET][SMALL]
[DEFAULT_RELSIZE:1]
[BP:S_L_L_INCISOR:second lower left incisor:STP][CONTYPE:HEAD][CATEGORY:TOOTH][SOCKET][SMALL]
[DEFAULT_RELSIZE:1]
[BP:L_R_CANINE:lower right canine:STP][CONTYPE:HEAD][CATEGORY:TOOTH][SOCKET][SMALL]
[DEFAULT_RELSIZE:1]
[BP:L_L_CANINE:lower left canine:STP][CONTYPE:HEAD][CATEGORY:TOOTH][SOCKET][SMALL]
[DEFAULT_RELSIZE:1]
[BP:F_U_R_PREMOLAR:first upper right premolar:STP][CONTYPE:HEAD][CATEGORY:TOOTH][SOCKET][SMALL]
[DEFAULT_RELSIZE:1]
[BP:S_U_R_PREMOLAR:second upper right premolar:STP][CONTYPE:HEAD][CATEGORY:TOOTH][SOCKET][SMALL]
[DEFAULT_RELSIZE:1]
[BP:F_U_R_MOLAR:first upper right molar:STP][CONTYPE:HEAD][CATEGORY:TOOTH][SOCKET][SMALL]
[DEFAULT_RELSIZE:1]
[BP:S_U_R_MOLAR:second upper right molar:STP][CONTYPE:HEAD][CATEGORY:TOOTH][SOCKET][SMALL]
[DEFAULT_RELSIZE:1]
[BP:F_L_R_PREMOLAR:first lower right premolar:STP][CONTYPE:HEAD][CATEGORY:TOOTH][SOCKET][SMALL]
[DEFAULT_RELSIZE:1]
[BP:S_L_R_PREMOLAR:second lower right premolar:STP][CONTYPE:HEAD][CATEGORY:TOOTH][SOCKET][SMALL]
[DEFAULT_RELSIZE:1]
[BP:F_L_R_MOLAR:first lower right molar:STP][CONTYPE:HEAD][CATEGORY:TOOTH][SOCKET][SMALL]
[DEFAULT_RELSIZE:1]
[BP:S_L_R_MOLAR:second lower right molar:STP][CONTYPE:HEAD][CATEGORY:TOOTH][SOCKET][SMALL]
[DEFAULT_RELSIZE:1]
[BP:F_U_L_PREMOLAR:first upper left premolar:STP][CONTYPE:HEAD][CATEGORY:TOOTH][SOCKET][SMALL]
[DEFAULT_RELSIZE:1]
[BP:S_U_L_PREMOLAR:second upper left premolar:STP][CONTYPE:HEAD][CATEGORY:TOOTH][SOCKET][SMALL]
[DEFAULT_RELSIZE:1]
[BP:F_U_L_MOLAR:first upper left molar:STP][CONTYPE:HEAD][CATEGORY:TOOTH][SOCKET][SMALL]
[DEFAULT_RELSIZE:1]
[BP:S_U_L_MOLAR:second upper left molar:STP][CONTYPE:HEAD][CATEGORY:TOOTH][SOCKET][SMALL]
[DEFAULT_RELSIZE:1]
[BP:F_L_L_PREMOLAR:first lower left premolar:STP][CONTYPE:HEAD][CATEGORY:TOOTH][SOCKET][SMALL]
[DEFAULT_RELSIZE:1]
[BP:S_L_L_PREMOLAR:second lower left premolar:STP][CONTYPE:HEAD][CATEGORY:TOOTH][SOCKET][SMALL]
[DEFAULT_RELSIZE:1]
[BP:F_L_L_MOLAR:first lower left molar:STP][CONTYPE:HEAD][CATEGORY:TOOTH][SOCKET][SMALL]
[DEFAULT_RELSIZE:1]
[BP:S_L_L_MOLAR:second lower left molar:STP][CONTYPE:HEAD][CATEGORY:TOOTH][SOCKET][SMALL]
[DEFAULT_RELSIZE:1]
Note: the above can also be applied to the GENERIC_TEETH* body templates, if you adjust the tooth sizes (for instance, in GENERIC_TEETH_WITH_LARGE_EYE_TEETH, you should set the RELSIZE of the eye teeth to 15). For sufficiently large creatures (e.g. dragons), butchering will also now yield 28 teeth, instead of only one.
[BODY:RIBCAGE]
[BP:1_L_TRUE_RIB:first left true rib:STP][CONTYPE:UPPERBODY][CATEGORY:RIB_TRUE][SMALL][INTERNAL]
[DEFAULT_RELSIZE:30]
[BP:2_L_TRUE_RIB:second left true rib:STP][CONTYPE:UPPERBODY][CATEGORY:RIB_TRUE][SMALL][INTERNAL]
[DEFAULT_RELSIZE:30]
[BP:3_L_TRUE_RIB:third left true rib:STP][CONTYPE:UPPERBODY][CATEGORY:RIB_TRUE][SMALL][INTERNAL]
[DEFAULT_RELSIZE:30]
[BP:4_L_TRUE_RIB:fourth left true rib:STP][CONTYPE:UPPERBODY][CATEGORY:RIB_TRUE][SMALL][INTERNAL]
[DEFAULT_RELSIZE:30]
[BP:5_L_TRUE_RIB:fifth left true rib:STP][CONTYPE:UPPERBODY][CATEGORY:RIB_TRUE][SMALL][INTERNAL]
[DEFAULT_RELSIZE:30]
[BP:6_L_TRUE_RIB:sixth left true rib:STP][CONTYPE:UPPERBODY][CATEGORY:RIB_TRUE][SMALL][INTERNAL]
[DEFAULT_RELSIZE:30]
[BP:7_L_TRUE_RIB:seventh left true rib:STP][CONTYPE:UPPERBODY][CATEGORY:RIB_TRUE][SMALL][INTERNAL]
[DEFAULT_RELSIZE:30]
[BP:1_R_TRUE_RIB:first right true rib:STP][CONTYPE:UPPERBODY][CATEGORY:RIB_TRUE][SMALL][INTERNAL]
[DEFAULT_RELSIZE:30]
[BP:2_R_TRUE_RIB:second right true rib:STP][CONTYPE:UPPERBODY][CATEGORY:RIB_TRUE][SMALL][INTERNAL]
[DEFAULT_RELSIZE:30]
[BP:3_R_TRUE_RIB:third right true rib:STP][CONTYPE:UPPERBODY][CATEGORY:RIB_TRUE][SMALL][INTERNAL]
[DEFAULT_RELSIZE:30]
[BP:4_R_TRUE_RIB:fourth right true rib:STP][CONTYPE:UPPERBODY][CATEGORY:RIB_TRUE][SMALL][INTERNAL]
[DEFAULT_RELSIZE:30]
[BP:5_R_TRUE_RIB:fifth right true rib:STP][CONTYPE:UPPERBODY][CATEGORY:RIB_TRUE][SMALL][INTERNAL]
[DEFAULT_RELSIZE:30]
[BP:6_R_TRUE_RIB:sixth right true rib:STP][CONTYPE:UPPERBODY][CATEGORY:RIB_TRUE][SMALL][INTERNAL]
[DEFAULT_RELSIZE:30]
[BP:7_R_TRUE_RIB:seventh right true rib:STP][CONTYPE:UPPERBODY][CATEGORY:RIB_TRUE][SMALL][INTERNAL]
[DEFAULT_RELSIZE:30]
[BP:1_L_FALSE_RIB:first left false rib:STP][CONTYPE:UPPERBODY][CATEGORY:RIB_FALSE][SMALL][INTERNAL]
[DEFAULT_RELSIZE:30]
[BP:2_L_FALSE_RIB:second left false rib:STP][CONTYPE:UPPERBODY][CATEGORY:RIB_FALSE][SMALL][INTERNAL]
[DEFAULT_RELSIZE:30]
[BP:3_L_FALSE_RIB:third left false rib:STP][CONTYPE:UPPERBODY][CATEGORY:RIB_FALSE][SMALL][INTERNAL]
[DEFAULT_RELSIZE:30]
[BP:1_R_FALSE_RIB:first right false rib:STP][CONTYPE:UPPERBODY][CATEGORY:RIB_FALSE][SMALL][INTERNAL]
[DEFAULT_RELSIZE:30]
[BP:2_R_FALSE_RIB:second right false rib:STP][CONTYPE:UPPERBODY][CATEGORY:RIB_FALSE][SMALL][INTERNAL]
[DEFAULT_RELSIZE:30]
[BP:3_R_FALSE_RIB:third right false rib:STP][CONTYPE:UPPERBODY][CATEGORY:RIB_FALSE][SMALL][INTERNAL]
[DEFAULT_RELSIZE:30]
[BP:1_L_FLOATING_RIB:first left floating rib:STP][CONTYPE:UPPERBODY][CATEGORY:RIB_FLOATING][SMALL][INTERNAL]
[DEFAULT_RELSIZE:20]
[BP:2_L_FLOATING_RIB:second left floating rib:STP][CONTYPE:UPPERBODY][CATEGORY:RIB_FLOATING][SMALL][INTERNAL]
[DEFAULT_RELSIZE:20]
[BP:1_R_FLOATING_RIB:first right floating rib:STP][CONTYPE:UPPERBODY][CATEGORY:RIB_FLOATING][SMALL][INTERNAL]
[DEFAULT_RELSIZE:20]
[BP:2_R_FLOATING_RIB:second right floating rib:STP][CONTYPE:UPPERBODY][CATEGORY:RIB_FLOATING][SMALL][INTERNAL]
[DEFAULT_RELSIZE:20]
Note: if you use the new ribcage, I recommend also changing BODY_DETAIL_PLAN:HUMANOID_RIBCAGE_POSITIONS -
[BODY_DETAIL_PLAN:HUMANOID_RIBCAGE_POSITIONS]
true ribs around heart
[BP_RELATION:BY_TOKEN:1_L_TRUE_RIB:AROUND:BY_CATEGORY:HEART:5]
[BP_RELATION:BY_TOKEN:2_L_TRUE_RIB:AROUND:BY_CATEGORY:HEART:5]
[BP_RELATION:BY_TOKEN:3_L_TRUE_RIB:AROUND:BY_CATEGORY:HEART:5]
[BP_RELATION:BY_TOKEN:4_L_TRUE_RIB:AROUND:BY_CATEGORY:HEART:5]
[BP_RELATION:BY_TOKEN:5_L_TRUE_RIB:AROUND:BY_CATEGORY:HEART:5]
[BP_RELATION:BY_TOKEN:6_L_TRUE_RIB:AROUND:BY_CATEGORY:HEART:5]
[BP_RELATION:BY_TOKEN:7_L_TRUE_RIB:AROUND:BY_CATEGORY:HEART:5]
[BP_RELATION:BY_TOKEN:1_R_TRUE_RIB:AROUND:BY_CATEGORY:HEART:5]
[BP_RELATION:BY_TOKEN:2_R_TRUE_RIB:AROUND:BY_CATEGORY:HEART:5]
[BP_RELATION:BY_TOKEN:3_R_TRUE_RIB:AROUND:BY_CATEGORY:HEART:5]
[BP_RELATION:BY_TOKEN:4_R_TRUE_RIB:AROUND:BY_CATEGORY:HEART:5]
[BP_RELATION:BY_TOKEN:5_R_TRUE_RIB:AROUND:BY_CATEGORY:HEART:5]
[BP_RELATION:BY_TOKEN:6_R_TRUE_RIB:AROUND:BY_CATEGORY:HEART:5]
[BP_RELATION:BY_TOKEN:7_R_TRUE_RIB:AROUND:BY_CATEGORY:HEART:5]
left true ribs around left lung
[BP_RELATION:BY_TOKEN:1_L_TRUE_RIB:AROUND:BY_TOKEN:LLUNG:5]
[BP_RELATION:BY_TOKEN:2_L_TRUE_RIB:AROUND:BY_TOKEN:LLUNG:5]
[BP_RELATION:BY_TOKEN:3_L_TRUE_RIB:AROUND:BY_TOKEN:LLUNG:5]
[BP_RELATION:BY_TOKEN:4_L_TRUE_RIB:AROUND:BY_TOKEN:LLUNG:5]
[BP_RELATION:BY_TOKEN:5_L_TRUE_RIB:AROUND:BY_TOKEN:LLUNG:5]
[BP_RELATION:BY_TOKEN:6_L_TRUE_RIB:AROUND:BY_TOKEN:LLUNG:5]
[BP_RELATION:BY_TOKEN:7_L_TRUE_RIB:AROUND:BY_TOKEN:LLUNG:5]
right true ribs around right lung
[BP_RELATION:BY_TOKEN:1_R_TRUE_RIB:AROUND:BY_TOKEN:RLUNG:5]
[BP_RELATION:BY_TOKEN:2_R_TRUE_RIB:AROUND:BY_TOKEN:RLUNG:5]
[BP_RELATION:BY_TOKEN:3_R_TRUE_RIB:AROUND:BY_TOKEN:RLUNG:5]
[BP_RELATION:BY_TOKEN:4_R_TRUE_RIB:AROUND:BY_TOKEN:RLUNG:5]
[BP_RELATION:BY_TOKEN:5_R_TRUE_RIB:AROUND:BY_TOKEN:RLUNG:5]
[BP_RELATION:BY_TOKEN:6_R_TRUE_RIB:AROUND:BY_TOKEN:RLUNG:5]
[BP_RELATION:BY_TOKEN:7_R_TRUE_RIB:AROUND:BY_TOKEN:RLUNG:5]
false ribs around heart
[BP_RELATION:BY_TOKEN:1_L_FALSE_RIB:AROUND:BY_CATEGORY:HEART:5]
[BP_RELATION:BY_TOKEN:2_L_FALSE_RIB:AROUND:BY_CATEGORY:HEART:5]
[BP_RELATION:BY_TOKEN:3_L_FALSE_RIB:AROUND:BY_CATEGORY:HEART:5]
[BP_RELATION:BY_TOKEN:1_R_FALSE_RIB:AROUND:BY_CATEGORY:HEART:5]
[BP_RELATION:BY_TOKEN:2_R_FALSE_RIB:AROUND:BY_CATEGORY:HEART:5]
[BP_RELATION:BY_TOKEN:3_R_FALSE_RIB:AROUND:BY_CATEGORY:HEART:5]
left false ribs around left lung
[BP_RELATION:BY_TOKEN:1_L_FALSE_RIB:AROUND:BY_TOKEN:LLUNG:5]
[BP_RELATION:BY_TOKEN:2_L_FALSE_RIB:AROUND:BY_TOKEN:LLUNG:5]
[BP_RELATION:BY_TOKEN:3_L_FALSE_RIB:AROUND:BY_TOKEN:LLUNG:5]
right false ribs around right lung
[BP_RELATION:BY_TOKEN:1_R_FALSE_RIB:AROUND:BY_TOKEN:RLUNG:5]
[BP_RELATION:BY_TOKEN:2_R_FALSE_RIB:AROUND:BY_TOKEN:RLUNG:5]
[BP_RELATION:BY_TOKEN:3_R_FALSE_RIB:AROUND:BY_TOKEN:RLUNG:5]
false ribs around liver
[BP_RELATION:BY_TOKEN:1_L_FALSE_RIB:AROUND:BY_CATEGORY:LIVER:5]
[BP_RELATION:BY_TOKEN:2_L_FALSE_RIB:AROUND:BY_CATEGORY:LIVER:5]
[BP_RELATION:BY_TOKEN:3_L_FALSE_RIB:AROUND:BY_CATEGORY:LIVER:5]
[BP_RELATION:BY_TOKEN:1_R_FALSE_RIB:AROUND:BY_CATEGORY:LIVER:5]
[BP_RELATION:BY_TOKEN:2_R_FALSE_RIB:AROUND:BY_CATEGORY:LIVER:5]
[BP_RELATION:BY_TOKEN:3_R_FALSE_RIB:AROUND:BY_CATEGORY:LIVER:5]
floating ribs around liver
[BP_RELATION:BY_TOKEN:1_L_FLOATING_RIB:AROUND:BY_CATEGORY:LIVER:5]
[BP_RELATION:BY_TOKEN:2_L_FLOATING_RIB:AROUND:BY_CATEGORY:LIVER:5]
[BP_RELATION:BY_TOKEN:1_R_FLOATING_RIB:AROUND:BY_CATEGORY:LIVER:5]
[BP_RELATION:BY_TOKEN:2_R_FLOATING_RIB:AROUND:BY_CATEGORY:LIVER:5]
total coverage - heart 100%, lungs 50%, liver 50%
This also makes the ribs behave more believably - it is impossible to injure the heart without first busting through at least one rib, and the lungs and liver are 50% covered, instead of 5%. I believe this is what was intended.