Wanted to add a resource field to another. Clicked on the "+" to add, marked it and after waiting for it to be in the list, i pressed Q, directly with pressing Q, the error showed up:

Die Mod YARM - Resource Monitor (0.8.203) hat einen Fehler verursacht, der nicht behoben werden kann.
Bitte informiere den Autor der Mod über diesen Fehler.

Error while running event YARM::on_gui_click (ID 1)
YARM/resmon.lua:550: attempt to index local 'site' (a nil value)
stack traceback:
YARM/resmon.lua:550: in function 'submit_site'
YARM/resmon.lua:1137: in function 'expand_site'
YARM/resmon.lua:1271: in function <YARM/resmon.lua:1259>