unfortunately I can not. I wasn’t the programmer on this only the artist and from what I am given to understand the game was programmed on an older version of unity and wouldn’t work when imported to newer versions and the computer that had that version and the source files is dead. However maybe you are running into the problem darthmrn may be having.
I think the problem with upgrading you are having is that one or more of the cards you are trying to combine are still in a deck. We weren’t able to get the game to not crash when you consumed a card that was in one of your decks. So you need to make sure they aren’t currently in one of the three presets. You can see what decks they are currently in when you click on them in the library. It is at the bottom of the info/pop up.