In that case, my version does not seem to know that it is supposed to be limited...
I don't seem to have any difficulty making the screen (e.g.) 950 px by 600 px
Are you referring to the "Small" and "Large" options in the settings menu...?

Ok, I got it to work if you make sure your grabbing the window that all the components are in first then after that's the size you want you can make your video larger. Thanks for the inspiration Per.

Glad you got it to work at your end too, - and that I wasn't delusional after all!
As an aside, the Photo Gallery sizing works exactly the same way.