I can't get to the neutral Imperial base in the south after I take out Page's Commandos(orange rebels) at Teks(purple imperials) When I go south to the base there is a wall across the path. How do I get to the Base??

It seems that your ally’s AI does a mess on this map, and build walls where it shouldn’t.
Just build a couple artillery pieces and cut your way through the nearby trees with them to pass this wall (works with carbon collectors too, but takes more time), that’s how I managed to finish this mission.

Yeah, same issue I had yesterday. Use artillery units, set them attackt he trees. :D Also, you can set neutral or enemy for that "player" and destroy they walls. :D So much fun.