I don't know anything about this error. There are two things you could try now:
1. Get Avedesk v1.5, It's the last stable build of avedesk (get it at avedesk.org).
2. If step one doesn't help, try posting at Aqua-Soft. There are a large number of active users
and developers there, who might be able to help with your problem.
If you want to stay with Yahoo, the shortcut widget should be available by default. You'll have to set the icons yourself, though; so don't expect the same images as in the screenshot above.

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