antherem: I think, but am not 100% positive, that Starport storage also counts against whatever limit this is. So you might try clearing out Starport once you're rich - get rid of all the crap artifacts, lifeforms, and low-value non-repair minerals, using the jettison function. Lifeforms are a waste of bytes in Starflight 1, don't even bother recording their biodata, let alone capturing them.
LordCinnamon: Well, this being my first play-through, it took a little while for me to realize the uselessness of lifeforms, so my optimistic scanning and capturing might have put some strain on starflight's memory, or something. But I can't see those being stored anywhere after selling them (so I can't clear them out either). I did clear out all artifacts, but that doesn't seem to have made a difference.
It seems likely that the problem is something with playing Starflight on DOSBox.
EDIT: oh, and did you scan and capture a lot of lifeforms? Because if not, then it seems unlikely to be a significant factor.
In Starflight 1, lifeforms are useless, so don't bother with them; besides shooting them with the laser if they attack you.
For those who have scanned a lot of them, I think you are correct on the memory problem, which seems to be related to the "Miner's Bug" I mentioned in another topic. Both have to do with Starflight's memory cache relating to the initial "random" aspects of the game. Key locations throughout the game have a fixed position, but everything else is randomized during the initial scan of the area. Once the scan has been made, the area "then" becomes "fixed"; in other words, the game remembers everywhere you've been!
Now, with that understanding, if you do too much scanning, exploring much of the surface on even a single planet... the cache fills up to capacity and starts doing strange things which usually leads to a fatal crash. I have personally done this by searching for Ancient Ruins on the (3rd?) Ice planet in the Arth System, having never even left the System!
Now for some words of advice: 1) Don't bother with lifeforms because minerals is where it's at. 2) Limit yourself to 1 or 2 landings on mineral runs, sticking to the mid highlands where most minerals can be found and exploring up to 30-50 clicks in all directions. 3) Make money by Planet Recommendations; know the qualifications by heart and send out those drones! 4) Make notes! Very important! If this is your first time playing... you know nothing! So, if you make records of where things are, the next time, should you fail to save Arth; you can proceed much faster. Especially with any Planet Recommendations you find! 5) If you need time to think about your next move... hit the Esc key to pause the game; game time will continue to pass if you just let it sit there, and you really don't have any time to waste!
I hope all of this helps!
This is Captain Kirk Romannof of the ISS Anec Nova, signing off! 8)