In the final round I had about 60 Crystite units, the other AI player had 5. During the final auction the base sell price was 136, and I set myself to buy as high as I could go in the time allowed (got to about 3500), but the AI didn't try to sell a unit, despite it being better for him to raise the final price.
So what I'm gathering is that in the C64 version, you were able to affect the final value of Crystite by trading a single unit? If so, this is mounting evidence that the alleged difference in final round price valuation between the Atari/C64 versions is a bit fishy. (And why, in your opinion, would it benefit the AI to make your vastly larger stockpile worth more? I'm just asking, lol.)
In the time I've played the C64 version, AI never sell
anything in round 12. I know for a fact that the devs have coded this for the AI in version 1.1 and beyond.