When you click on the tab at the right side of your VDA, Chris, it brings up your inventory. That way you can use the items in it while you have the VDA screen active. Otherwise the inventory is not accessible until you close out the VDA.
As for drawing the maps, I haven't gotten that far yet (I'm still winning enough money to outfit myself!), but have you tried using the laser pen? I don't know if that's the solution or not, but it's worth a try.....
"Once you give up integrity, the rest is easy." Anonymous