If you could assign an NBT file to Entities would be Awesome
would make Exporting and Editing NBT data for Entities much Easier.

Fixed by Authvin for 1.12.2 v9, also ported to 1.16 for 0.0.17, though spigot still needs some fixes (see #752 ).

Thanks for reporting. I've only tested with .txt files recently, will test with .nbt as well.

Does this affect Forge and/or Spigot?

Also only tested on Spigot.

Currently it worked like this:
Blocks only Accepted NBT files, and Entities only TXT

Will need to implement either a library in the common layer for reading nbt files, or use forge/spigot-specific methods to read nbt files for each platform. Not as quick and easy as it sound, unfortunately. Since there is a way to work around this, will do this after 1.13. Will update the comments in the configs to clarify though.