I will eventually add a full resolution menu, but I wanted to get something out quickly. Today's build should have a resizeable window. Please enjoy, and let me know if there are any issues. Thanks!
A minor bug I found: Having the "Repeater" selected for purchase, the ghost of the repeater will still fire real pellets. Very useful if you can't afford a second repeater yet, but probably not intended.
Thanks for noting this. I have since fixed it, but am putting a few more features into the next build. I'm going to miss this little exploit, though :P