Hi to all,
I have a desk with cards of which I want to draw one and only one. Is it possible in some way to block the choice of a second card as long as the first one is selected?
Thank you for your support!
Panther 2010 
I’m not sure exactly what you mean by “selected”, but say you draw a card and drag it somewhere on the table to look at it. And that it sits there until you “play” it after which it is presumably “discarded” to some other discard deck that it sits in.
It sounds like what you want to prevent is the player drawing ANOTHER card during that time. So if set your map to send a trigger e.g. “MovedOnMap” (bottom entry when you double click the entry for your Map), you could then set up your cards to respond to that – a card finding itself “in play” could mark a Global Property “IsCardInPlay” to be 1 or “true” or something. Except that it would first CHECK the IsCardInPlay to see if it was ALREADY set to 1 or true, and in that case that means it’s “uh oh I am the illegal second card” and it would promptly “Send To Location” itself back to the draw pile (and perhaps do a “Report” trait of “Hey $PlayerName$! You can’t draw another card until play the one you already have!”) – I believe this would all take place without ever actually even showing the player what the card was. And then when a card is PLAYED properly it would set the IsCardInPlay back to 0 so then it would be legal to draw a card again.
It’s possible I have misunderstood your use case, but hopefully this gives you some ideas.
Best,
Brian
Hello Brian,
many thanks for your answer to my question.
I regret not exposing my problem clearly. I try to remedy. In a private window a player may choose one card from eight cards. Cards are face up. Once the card is chosen, it is flipped (masked) and then sent to another window where it will be played and then sent back to the deck. It should be avoided that the player can select a second card until the first has been returned to the deck.
I will try your suggestions as soon as possible. I think they will work
Be well
John. 
How does the player choose the card? (Does he “right click” on it and pick an option? Does he drag it from one window to another?)
Solved. Now I have all the eight cards in a fixed position on a private window and do not use a deck any more. All works well.