Hi vezerid,
Thank you as well for your help. Please see response to Duke, below for an
explanation.
First time I've used this forum for help and I'm thrilled you are all here.
It's kind of like a suicide hotline. Even if your problem isn't solved, just
knowing someone else is out there and gives a damn makes a difference! :)

"vezerid" wrote:

This is probably because it is still text and cannot be recognized as a
number. Are the numbers left aligned?
Try the following:
Enter the value 0 in a separate cell. Edit|Copy the cell.
Select the imported numbers. Edit|Paste Special... Click the Add button
and OK.

Does this help?

Kostis Vezerides