Building my train part 3

 I assumed that the train I have would be easier now that I'm able to pick out parts...the only problem is that there are so many pieces missing i can't even start blue unit b or the baggage cart.  I'm loving the train but the missing parts are hard to discern if they actually came vs I just lost it.  Here's today's progress 

Above: no roof pieces are present@

Above: not ready for these roof pieces because I dont have the plates

Above hard to get rear side and back pieces together without breaking the 3 sides

I sent an email and will wait for a response..they do move quickly to fix per reviews on internet!