Thank you very much, it works great. I take the occasion to express my admiration for people like you who do listen to others and help them.
I tried with my own file and the result is as I want it. Just one more question, but don't spend much time on it, only if you have a simple answer: In cells with a formula, it seems that the format has been a little bit modified: Initially, zero result values are not displayed in my sheets, but after saving with fpspreadsheet, there are 0's.
And a suggestion: When I got the error message about "not a valid worksheet name", this message was in a window which popped up from the IDE. It would be very handy if I could select/copy (a part of) the message for searching the internet, but I can't. Maybe this can be modified simply, or is there a good reason not to allow it?