I think I have tracked the problem.
Here are the tests I made:
1. Unpacked it into "D:\" (folder was "D:\DFLang diagnostic"), used standard defaults.txt with relative paths
It worked2. Changed dafaults.txt to use absolute paths
It worked3. Changed "DFLang diagnostic" folder to "DFLangdiagnostic", and updated defaults.txt
It didn't work!4. Changed folder name to "DFLang", updated defaults.txt
It didn't work!5. Changed folder name to "DF Lang", updated defaults.txt
It worked!6. Changed folder name to "DFLang", and reverted defaults.txt to use relative paths
It didn't work!Here are contents of log.txt:
uni: <{D:/DFLang diagnostic/languages/dwarf.txt}>
str: <{D:/DFLang diagnostic/languages/dwarf.txt}>
file: <D:/DFLang diagnostic/languages/dwarf.txt>
text: <D:/DFLang diagnostic/languages/dwarf.txt
>
uni: <{D:/DFLang diagnostic/languages/dwarf.txt}>
str: <{D:/DFLang diagnostic/languages/dwarf.txt}>
file: <D:/DFLang diagnostic/languages/dwarf.txt>
text: <D:/DFLang diagnostic/languages/dwarf.txt
>
uni: <D:/DFLangdiagnostic/languages/dwarf.txt>
str: <D:/DFLangdiagnostic/languages/dwarf.txt>
text: <
>
uni: <D:/DFLang/languages/dwarf.txt>
str: <D:/DFLang/languages/dwarf.txt>
text: <
>
uni: <{D:/DF Lang/languages/dwarf.txt}>
str: <{D:/DF Lang/languages/dwarf.txt}>
file: <D:/DF Lang/languages/dwarf.txt>
text: <D:/DF Lang/languages/dwarf.txt
>
uni: <D:/DFLang/languages/dwarf.txt>
str: <D:/DFLang/languages/dwarf.txt>
text: <
>
Conclusion: It seems that it doesn't work if folder path doesn't contain a space!Absolute / relative paths in default.txt doesn't matter.
May need more tests with more complicated paths.
The bug has been struck down!Hope it helped.