[trainman707]

Dave,
It appears that your doors may have been cut too short in your kit.  Hard to tell, but mine seemed longer and fit perfectly.  Haven't had any problems
that way.  I think I would ask the store where you purchased the kit from for a replacement kit or at least a replacement for the doors.
 
Here is a picture of how mine looks after being built.  We had a burger stand in California that was called "The Octagon" so had signs made to reflect
that on our kit.
 
 

 

[trainman707]

Yes, there is a door frame. It's hard to see if it was installed from Dave's photo
of only the back side. That might do the trick.