1) The number of card drops remaining is the actual number of cards remaining based off of the profile that you're signed into. (I still have 725 card drops remaining myself).
2) The timer is there for when the application will check to see how many card cards is remaining for the game (or games) that it's idling and how many drops total remains. It has nothing to do if and when you'll get the actual card since that's completely random for each game.
3) All there is left is the portal version which can be found at http://www.steamidlemaster.com/idle_master.zip (not sure if you've downloaded idle master before or after the March 2nd announcement or not)

thanks!!