Hi there,
Firstly to point out that the filename reported by Pegasus Mail (the Dot) is not done when you double click the attachment entry. PMIcal does not get involved until the user causes the attachment to be associated with an application, and then the application can be invoked with the extracted file. This is identical to the Mail filter rules where an application can get triggered by a rule firing, and the *.CNM file path details are passed as a parameter (%s).
The problem is that a user on the Pegasus Mail Attachments list page will select a part they are interested in and then click Open. It is silent (failed Open). If they click Save they get a Save dialog and can Save As anything they want. But how do they determine what the content of the file is? Well they can do a Raw View, and wade through all the Mime parts and then do a selective copy of the vCalendar content, invoke Notpad and save it. Then in Windows Explorer, find the just-created file and double-click it (if the file association with PMIcal is present) and wake up PMIcal. Way too much.
So I am doing a review of the various processes involved in PMIcal and may well re-design the workflow
I hope this starts to clarify the problems, generated by Microsoft mainly, are causing me. P.S The same problems, to a lesser extent, occur with vCard streams from exporting Microsoft and Apple Contacts.
Martin