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from the title of the post, I deduce you overwrote a number of files with blank version of themselves?
That works in general, but you probably missed other files that are referring to those old values...

could you post a bit more what you did so far in your mod?
 
added some character to the ROM setup file, added more families for rome in the default.txt, extended the number of allowable families in the defines, anddd i used some of the files from Bloodlines 1.4( just used it as a base to make my own bloodlines) and HIstorical Units and Military Traditions.,this mod is for my own personal use though,
 
  • You made quite a lot of changes to the 00_ROM.txt 100's of lines.
    • From what I see there you MIGHT have made an error in the brackets somewhere shortly before line 1159 and/or at the end of the file.
    • You made some mistakes on effect scopes (value vs. character). make sure to have a SCOPE:yourCharacterVariable or actual character scope. e.g. around line
      1171
  • your font_icons might not have the proper encoding.

  • You made a bunch of modifiers that have no icon.
  • setup/main/00_default.txt : check around (or just before) line 1105. you might have bracket closing issues.

check those and see what the logs say. A big tip: don't change everything at once when doing such a change.
  1. do a 1-person/family/modifier trial. 1 new/updated object at a time. This will allow you to make more sense of the logs.
  2. when everything works, go expand the values. Test often.
  3. Copy the mod folder as a backup, so you can go back. When making large changes, this is a must. Consider using a code repository.