To solve the resize problem in Poker Stars, open the file:
>~/.cxoffice/pokerstars**/drive_c/Program files/PokerStars/user.ini
(where pokerstars** is whatever you named the bottle)
and add the line f5redrawtable=1
to the section labelled [options]
Then when the resize artefacts show up, hit F5, problem gone! :)