Actually with only URO enabled, I also enabled WME Color Highlight. This didn't trigger the problem. After that I enabled WME-Add-Ons and the problem triggered immediately. I assumed that the WME-Add-Ons script was the actual trigger.
This time I started out with only URO enabled and working. I enabled WME-Add-Ons and WME continued to behave good. Then I enabled WME Color Highlight and got the problem back again. So it seems to be something more than just one other script together with URO.
Disabling all scripts but URO solves the problem but by just adding WME-Add-Ons againg or WME Color Highlight (both not required any longer) makes the problem come back.
The way to reproduce the problem (if the URO menu doesn't start to duplicate it self over and over) is to zoom in one level (using the mouse to click the + sign) and then pan the map (using the mouse). After this, panning gets all wrong and zoom indicator doesn't change when using +/-.
