Doolittle, any AI in your squad can unlock it if you command them to. Simply hit F1-F12 to bring up the appropriate soldier, press 6 and then the UNLOCK option should be on there somewhere.
The factory with the ladders has been the same since RTS-1, but the ladder is actually useable now. It used to be if you tried to climb it you'd get stuck there until someone killed you. I can't remove the option for it, and I haven't spotted another building that suits my fancy for that.
Also, the squads that appear at cities are reinforcements that will stay and guard the city. You should also get an Ammo and Repair truck there after holding it for a certain period of time.
I'll soon be adding AI squads back to the game, but there will be a much greater method of control over them I hope. I'll be using OnMapSingleClick to position markers for them (like in RTS-2) but you'll have more flexibility on moving them about. Basically teams will be able to create up to a certain number of independent squads (this can be limited at the Command HQ) and then tell them each separately where to go. In RTS2 you can only create pre-defined squads, like Armored AA and Tank Squads. I hope to greatly improve it.