I've found a way to avoid fractal body bug.
Make creature, but with only upper\lower body, like:
[BODY:BASIC_2PARTBODY]
Put all tokens that stand for all castes you gonna make - like [CANOPENDOORS], [INTELLIGENT], [EQUIPS] etc.
Also, don't forget to specify the material of body.
Then make castes. Add whatever body parts, but not upper\lower bodies, cause you know why.
I tested it just minutes ago, works well.
Example of creature:
[CREATURE:GENEZIS]
[DESCRIPTION:Researchers gonna research.]
[NAME:genezis:genezises:genezis]
[CREATURE_TILE:'C'][COLOR:6:0:0]
[CANOPENDOORS]
[BIOME:ANY_LAND]
[EQUIPS]
[PREFSTRING:unique DNA]
[BODY:BASIC_2PARTBODY]
[NO_THOUGHT_CENTER_FOR_MOVEMENT]
[TISSUE:BRONZE]
[TISSUE_NAME:bronze:bronze]
[TISSUE_MATERIAL:INORGANIC:BRONZE]
[MUSCULAR]
[FUNCTIONAL]
[STRUCTURAL]
[RELATIVE_THICKNESS:1]
[CONNECTS]
[TISSUE_SHAPE:LAYER]
[TISSUE_LAYER:BY_CATEGORY:ALL:BRONZE]
[BODY_SIZE:0:0:200000]
[BODY_SIZE:1:168:3000000]
[BODY_SIZE:12:0:9000000]
[ATTACK:PUNCH:BODYPART:BY_TYPE:GRASP]
[ATTACK_SKILL:GRASP_STRIKE]
[ATTACK_VERB:punch:punches]
[ATTACK_CONTACT_PERC:100]
[ATTACK_FLAG_WITH]
[ATTACK_PRIORITY:MAIN]
[ITEMCORPSE:STATUE:NO_SUBTYPE:INORGANIC:BRONZE]
[ITEMCORPSE_QUALITY:5]
[DIURNAL]
[SWIMS_LEARNED][SWIM_SPEED:2500]
[BABY:1]
[CHILD:12]
[CASTE:CREEP]
[BODY:BASIC_3PARTARMS:TAIL_STANCE:BASIC_HEAD:2EYES:2EARS:NOSE:HUMANOID_JOINTS:5FINGERS]
[TISSUE:BRONZE]
[TISSUE_NAME:bronze:bronze]
[TISSUE_MATERIAL:INORGANIC:BRONZE]
[MUSCULAR]
[FUNCTIONAL]
[STRUCTURAL]
[RELATIVE_THICKNESS:1]
[CONNECTS]
[TISSUE_SHAPE:LAYER]
[TISSUE_LAYER:BY_CATEGORY:ALL:BRONZE]
[CASTE_NAME:creep:creeps:creep]
[MALE]
[CASTE:CREEPCHAN]
[BODY:BASIC_3PARTARMS:BASIC_3PARTLEGS:BASIC_HEAD:2EYES:2EARS:NOSE:HUMANOID_JOINTS:5FINGERS:5TOES]
[TISSUE:BRONZE]
[TISSUE_NAME:bronze:bronze]
[TISSUE_MATERIAL:INORGANIC:BRONZE]
[MUSCULAR]
[FUNCTIONAL]
[STRUCTURAL]
[RELATIVE_THICKNESS:1]
[CONNECTS]
[TISSUE_SHAPE:LAYER]
[TISSUE_LAYER:BY_CATEGORY:ALL:BRONZE]
[CASTE_NAME:creepchan:creepchans:creepchan]
[FEMALE]
[ATTACK:KICK:BODYPART:BY_TYPE:STANCE]
[ATTACK_SKILL:STANCE_STRIKE]
[ATTACK_VERB:kick:kicks]
[ATTACK_CONTACT_PERC:100]
[ATTACK_FLAG_WITH]
[ATTACK_PRIORITY:SECOND]
As you can see it haz two castes - legless males and full-humanoid females. And yeah, they're based on colossus. I just had a sudden idea, implemented it and it worked so far. Im doubt about [NO_THOUGHT_CENTER_FOR_MOVEMENT], but anyways.
Also, don't know if somebody already posted it, just saw a genetics thread few months ago, and there was this fractal bodies stuff.