The Print Message applet does not actually print anything – it produces a HTML view of a message, including details of attachments, which the user may print manually. Only the summary is printed. No attachments are printed.
I gather from your post, and the message sent to the support account, that you are not actually using this applet. You appear to be having a problem printing certain PDF attachments from received GroupWise messages, with error messages like ‘Insufficient data for an image’ and ‘The document could not be printed’. You mentioned these messages are coming from the Adobe Acrobat Reader.
It sounds like you are trying to print corrupt PDF files. This has nothing to do with Formativ (or probably GroupWise, either). I would suggest you contact the person who sent you the PDF and ask them for fresh versions. You could also try re-installing the Acrobat Reader.