R J's dashboard

Have used Skitch for a while but the drag feature has stopped working, it will not drag a snapped image to iPhoto, mail e.t.c or any of the apps it used to.
On OSX 10.4.11 and nothing I'm aware of has changed and it gives an error warning saying "unreadable files 0" in iPhoto or nothing when I drag into Mail
Snaps, saves and recalls the image OK.

I'd be grateful for any solutions
Many thanks