Hey there. I recently found a solution to fix the lag. If you press Q and go to the section to clean up everything for Admins, just clean up everything. After doing that, all Signals and Lights are gone, but you have much more FPS as before. It seems, that all that Lights and Signals in this Map causing the lag.

Hope it helped! To me it works fine, but it's sad that all signals and lights have to "go away". :/