As with Mag Max, it seems that there was another conversion in the works for Breakthru, which saw a terrible release on the C64 in the end by US Gold.
Canvas were working on a Breakthru conversion for US Gold, but for reasons currently unknown, it was abandoned. Ironically, both Mag Max and Breakthru in their release versions – featured music by Fred Gray!
Graphics were being handled by Pete Graylish, who had produced various graphics on the C64 – including the loading screen to Miami Vice.
He unfortunately couldn’t recall anything about the conversion or what happened, but did provide this rare unfinished loading screen. Maybe the game was cancelled very early on perhaps?
If you know more, please get in touch!