Got another one here.

Error while running setup for entity prototype "underground-belt-L1" (underground-belt): next_upgrade target (fast-loader) must have the same grid alignment (bounding boxes aren't compatible or tiel_width/tile_height aren't compatible).

Thanks for the hard work!

can ya tell me what other mods you using? I can't recreate the bug :/

If I deactivate Loader Redux it works just fine, so that's my guess where the issue is.

yea, that's sadly a thing. Don't know how to fix that yet.