Map cant load

I try to make a new map for the game The map is 30% done and I saved the progress then I "installed" new buildings from other maps. Then I restarted the map and it showed me this...

Please help I dont want to restart again

 

The mission the game is referring to is your .mis file in your levels folder. make sure you have renamed all of the level directories correctly.

Also make sure that there is actually a .mis file in there.

 

Im having the same problem and where would i put the folder for my level i only have the art folder and the mis file how would I the structure of it is its in the content levels folder then in the folder is levels/testlevel/all da shit. I need help as i get the same problem.