COPYCLIP doesn't work

Hello,
I have problem with a file I'm working on in BrisCad 20 Pro. I can't use COPYCLIP on anything that is in the file. Popup shows up saying that operation has failed and here's what shows up command bar:

Translation:
_copyclip
selection
Can't create bitmap format. Try decreasing scale of image export.
Unallowed for this type of proxy: RbctDrawingObj - "RBCTDrawingObjDictionary"> (5A1C3)

Exporting everything as block to a file doesnt work either, same error.

How do I fix that?