Is it possible to change the window size.
I have a dual screen setup so fullscreen is not possible.
Can I change a value to increase the size of the window

Unfortunately, there is no easy way of making the game screen bigger without it slowing down *roughly* proportionally to the size you want to stretch it to.

I apologise for the inconvenience. It is possible though, to for example wrap around some functions in helpers.py to double-size (there is a specialised function for double-sizing something) the game to 1280x960 if that sounds interesting. I'm not sure how much more grunt it'll require, though.