Current Version is not compatible with Lootr.
The cause is believed to be the tower generation code and how the spawning of chests is handled.

@JMilamber Look at https://www.curseforge.com/minecraft/mc-mods/lootr Description, which describes chest generation methods that are compatible.
Also check out the new experimental version on the lootr discord which may fix problems already.

Thanks to @Romoslayer on Discord for letting me know about the incompatibility.