I think this game is checking the byte count of "probably" files.
It is unknown whether it is the unpacked file unit or the Data.pck unit.
First try matching the size in individual file units.
For example, if Quest.sdb is 16000 bytes, try repacking to have the same file size.
Example) Repack Quest.txt, fill in 400 bytes with 0x00 if it is 15600 bytes.
Therefore, you can only adjust by translation what becomes larger than the original file size.
Also, "D" in Data.pck must be in upper case (updated tools will output in upper case).
I am also working on translating into my native language, but it is a series of trial and error.
First of all, please try from what you can do.
As a side note, sdb's repacker does not reproduce the original file completely.
Because the original file is adjusted file size, unnecessary data may be written (please check in other languages).
Therefore, as mentioned earlier, please make the original file size the same as the repacked file size.
I wish you the best of luck.
It doesn't even work by changing another language. If you can make it work with your language, let us know. Thank you