Better End handles models/textures in a different way causing conflicts.
https://hastebin.com/pukamenowa.less
This causes the textures to appear as missing textures.

This is primarily an issue with Paul's BCLIB Features if you could add support that would be great.

Linked issue
paulevsGitch/BetterEnd#319

Try updating to the very latest version of both BCLib and BetterEnd, because I worked with the devs of these mods to resolve this issue a couple months ago.