Started up teh 10/12 version at the start of the mission (so only my guys are visible no moves made). Had no problems with squadies 1-4 but for some reason 5 would not show. It was a new rookie I added, not sure if that matters or not.
I get the same error IF I turn on the trainer before I load the game.
Way i solve it is:
1. load the editor wait for the ok button to appear, DO NOT PUSH IT YET
2. Load the game
3. At the GAME menu alt tab out click ok, wait a couple secs for the editor to load, when it's loaded and you see game running at the bottom push F1 and your good to go.
[Edited by L-Long, 10/12/2012 11:52:10 PM]