Dopus halts for unknown reasons (Edit: Tortoise 1.6.6)

I send a support request already, but Greg was unable to help any further.
So my question to the community:

DO constantly freezes at unexpected moments.
When DO is visible, a busy hour glass cursor appears, and nothing is possible anymore.
When DO is iconized on the windows taskbar, it tries to popup, but doesn't get any further than part of the full screen,
having the underlying screen shining through.

After restarting DO works again for a while.

My working lister layout is three tabs locally and three tabs pointing at a SFTP server.
Maybe this has something to do with the problem.

When I close the DO with right mouse click, a dump is created.

It only happened some time ago. Trying to remember what changed lately:
I upgraded to version 9.5 and I installed DO on my new SSD (Intel X25-M Postville) after a fresh reinstall of XP.
(Instead of on my raid harddisk as before)

Any suggestions on solving the problem or how to do further investigations?

The first measures would be to look through this FAQ:

[Crash, exit or high CPU when right-clicking certain files)

For anyone else following this thread, it seems to be the same TortoiseSVN 1.6.6 issue as in this thread, judging by Kurdy later post there.