You could try to just put your mouse outside the focus of that browser. Which i dont think in windows you can set that type of focusing, or anything close for that matter. I dont think the version of the browser you are running has got the correct API or code or something to hide the mouse for you right now. However, i could be wrong (probably am) and it's windows being blind to its own API (most likely the case...85%).
Odds are sadly your screwed. You do realize you dont have any control over windows and how it behaves dont you??? Just install the old version...whatever you do dont go back to IE.
You could however jump in the registry and possibly make the cursor hide whenever your browser ONLY is in focus...how would you do this??? I have no clue, as far as i have delt with the registry your pretty powerless to FIX problems to that extent.
Good luck for real.
