Minor bug when making layered font

Glyphs
1

I’m making a big family of layered fonts. After adding twenty-second master, I get the incompatibility mark even thou I didn’t have it while making all of the previous styles (and, of course, all of them are incompatible).
I can’t yet upload images so here are some links:
21 masters: http://i.imgur.com/Zy93kct.png?1
22 masters: http://i.imgur.com/vYPXCVH.png?1

And bdw it would be great to have some visual distinction in toolbar icons.
Maybe something like in the Font Info window?

2

could you send me the .glyphs file? (to support [at] this domain) Maybe only one glyphs?

3

Actually problem disappeared after adding another master. So it must’ve been a fluke.