Problem solved. I shut down the computer and did not look at it for a day. Just could not face it. Today I was able to solve the problem (conflict with COM4) with the help of a friend by phone. I would not have been able to do it myself. I will now write down how it was done, just in case it happens again.
So, back to weaving now :-)
I want to finish enough to make a cushion cover, cut it, wash and press and see how it comes out. I'm not sure how this will work as warp is cotton and weft is Tencel.