I was able to produce the "Sorry! The application Flickr Free (process
com.zmosoft.flickrfree) has stopped unexpectedly.  Please try again.
Force close" bug by doing the following:
1. Going into one of my groups.
2. Tapping a thumbnail to view a photo.
3. Attempting to download the photo before it loaded by bringing up
the menu and tapping the download button.  I had been experiencing a
few seconds of delay due to slowness on either Flickr's end or my
provider's end.
Hope this helps!
-- Dan