Thank you for giving the game a try even it's not your thing.
The first issue sounds like a bug. I quickly checked it, but couldn't reproduce it for now. So you should always be able to activate the power when you have at least one hand card (you can also activate it with full hand). And then you should be able to drag one of your hand cards in the above "dropzone" (border) to upgrade it. However we already have plans to redesign the entire screen and the input, because currently it's kind of overcomplicated and the player can't see the enemy pile while upgrading.
Thanks for pointing out the naming issue. We will discuss it and might reconsider our naming. I guess we should decide whether to go for correct/meaningful Norwegian names or go for full fantasy names. For now we took something in-between, because the names sound cool to us (we don't speak Norwegian) :D
Thanks for the input. We really appreciate it!