Well, I create a new installation of wordpress and added both MinervaKB and User Role Editor, and things worked fine. I figured something is wrong with my original site. I disabled all plugins except the 2 on the original site, still problem is there. I reset User roles from your settings menu, still problem is there.
I deleted all role related plugins (Members, AAM – but both were all the time deactivated) and deleted yours and reinstalled only yours. Things started to work again. I only noticed that the Posts Edit pop still showed ids of taxonomies.
So i guess i have to start enabling things again one by one and see if anything happens. It is stability that i am looking for, and i will not install other role related plugins because i am trying to stick with User Role Editor. I will keep you posted.