Question 1 - You probably need to use that little screw that everyone thinks is a idle screw. It's not an idle screw but an adjustment you can use to keep the thing from sticking like you describe. You have to be careful and not adjust to much, but the idea is to get the butterfly off the tb bore. Just work it carefully until the sticking goes away. Now, the engine will have to relearn idle after the adjustment.
So, my suggestion is to disconnect the battery......Make the adjustment until the stick goes away. Reconnect the battery and crank her up. Let the truck idle for around 2 minutes without pressing the gas....Put it in gear and let it idle for another 2 minutes....Take it out of gear and run the ac full blast for 2 minutes...now back in gear for 2 minutes....the idle should be around 750 RPM's....if not, you adjusted the screw too much...