Board Game Arena

Hi, I've had some issues with using the orient express card from tier 1 (the card that gives you the ability to use that card as any colour gem and you and you assign it to a card within you hand.)
I can afford to buy the card, so i purchase it, and then it won't let me click it on any of my playing area to use it. How do you play this card on BGA?
Thanks for any help

You need to already have bought at least one card of any colour before you can buy those grey/joker cards.

And then when you buy the grey card, along the top (on desktop) all the cards you've already purchased will appear. You then need to click one of those already purchased cards to indicate what colour you want the grey card to become.

I had the same issue and it was not letting me copy to another color that I had. I clicked on every part of the cards I had and it wouldn't let me add the grey card.