By trial and error I have figured out that you need to hold down Ctrl in order to select multiple columns. I like this, but unfortunately not documented anywhere to my knowledge
I have the same problem. In my case SCID crashed for some unknown reason while I had unsaved games in the attached database, and now I can't open the database.
Even better would be show the annotation symbol next to the arrow on the board. Then you don't rely on the variation window to get the feature.
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