Sorry, it actually works GREAT on the Electron!!! Only VERY minor issue is the instructions (MODE 7) don't display correctly, but that's being picky!
Thanks Greg for your comments, they are really appreciated. I can't take credit really, I cobbled bits and pieces from other games, notably ones authored by Mike Goldberg that were published in The Micro User. I certainly recall drawing the title screen as being great fun to do. I should revisit it for further inspiration for any other projects I have in mind!