The table width doesn't seem to be as big an issue as I thought. At least when the uploaded images have a sensible size, tables seem to adjust to them nicely.
I tried one more time to make a table to solve the problem, but in a test page User:Claus_chr/Test. Would this work? (apart from the <br /> problem - I havent found out what to do about that yet.)
Update: As a matter of fact I don't need the br tags at all - I just misread the wikimedia docs.
Q: Would this work? A: No. See 1. Can you keep the pipe ("| ") in one unit with the rest of the cell? If you do, then modified script can give something like this.
P.S. I should concentrate on my report now. Can we discuss the rest later? Thanks for your answer.