I started using Voxatron today and noticed something strange with the designer UI.
Options near the bottom of the screen are cut off, both in fullscreen and windowed mode.

Am I just being stupid and can't figure out how to scroll, or could it be something to do with my resolution or something?

Are you using Windows?

Yes

I have seen voxatron 3.5 been displayed inconsistently on Win laptops with most recent version of Win10 and up

Another Windows 10 user here, just to confirm:

I have two monitors so I was able to check if the resolution was the problem.

Believe it or not voxatron allows you to render it in a larger resolution than the screen. My smaller screen can see it if I use the larger resolution but, just as a warning, it makes everything small and blurry.