Hi Luka,
(sorry for being unresponsive lately, i spend a lot of time on the road
and have loads of other work to do...)
As for your problem: This seems to be (another) CSS-related issue.
IMHO it's not the script having problems determining the width,
however - maybe some CSS "trick" is needed here.
If the map shows up correctly with the width given in px units,
the script seems to be working fine.
I wonder if some javascript "magic" could do the trick,
but i'm far from being a JS expert.
Maybe someone else here can help out on this issue?
cheers, Frank