I've been trying to get the slideshow mode in Picasa2 to work, but it seems like it's relying on IDirectDrawSurface->Lock() to return DDERR_SURFACEBUSY if the surface is already locked. If this call doesn't return the error, it seems to keep hammering the function until it does. It then proceeds to hit a stack overflow condition somehow and dies. :)
I think it's a bug in Picasa, but my ddraw-surface-lock.diff patch in wine-patches fixes this behaviour (but not the feature, unfortunately).
Note that now the slideshow mode now just terminates without error. I'll keep on looking to see what's happening.
Matt.