This should be the final version. I've tested it, and it all seems to work. I did have a sequence of movers on route to Objective 4, but something broke and I thus deleted them all - now replaced by fences (sorry, I'm not sure what went wrong - the map just refused to load, so I guess there were a few errors with the mesh).
Objective 4 has be re-routed along a separate path away from Objective 3 to avoid confusion. There's also a sequence of barriers in place to further limit confusion. I'm hopeful the map is now glitch-proof - least I could find none. Solbender garages are now also in place. I've also placed a few barriers along the way (mostly barrels, but minus the movers

Hopefully the FPS problems have been sorted - I had only minor lapses on my laptop and that's not particularly powerful.
Enjoy.