Re: Huge gaps in this history
Ah the things that you could do with a BBC Micro! Actually called the British Broadcasting Corporation Micro after Brown Boveri Corporation got upset.
In the early 1980s, before the existence of the IBM PC, I worked for a company producing full-screen interactive video training software using a BBC Micro with a video card connected to an analogue Philips laserdisc player (12" discs like a vinyl LP in size). Analogue was fun, not as easy as asking for a digital file - you had to tell the disc where to seek to and then add in a fudge factor for the resulting overshoot and rebound of the playback head.
And don't mention MSX. I was a founding partner in Salamander Software back in the day and with every major Japanese electronics manufacturer signed up it looked like a no-brainer to develop for. It didn't end well.