...when I stamp on a photo or on a piece of paper and then my complete project is ruined! Well... I got the solution now... I am sure I am not the first one but I think of myself as a clever girl:
stamp with Stazon on an overheadtransparency (you can of course also use the one for the printer but I prefer to keep those for printing)and position it on your project before putting that stamp with the final print on your project!