These are games and programs that I only ever seen working fully right in a single machine.

Prehistorik 2: the overworld's position flickers when scrolling. I first seen it in WinXP with pentium 3 computers, and I see it on my machine as well; there was a single msdos or freedos + particular TSR combination that made that part work right here, but I got it only once and cant remember it anymore. My guess is CPU load/timing? After all the clock is unlocked in this system, but I dont remember if I lowered it or not. The one part that is nearly guaranteed to have display problems is the blue menu for passwords and game difficulty; screen tearing, shaking, the letters drag with the background... That only worked right in some old computer I cant access anymore, not even dosbox seem to do this one right.

Kgen98: 16bit mode only worked in an old Compaq Deskpro Pentium 2 computer. Tried an older Pentium 1, a later Pentium 3, didnt work on either. No effect with nolfb, no effect with a tsr that reports vbe2 instead of vbe3. I wonder if has anything to do with an unsupported scanlines mode for some reason, but thats just an aside.

No$gba: it only worked in an old Compaq Deskpro Pentium 2, and not even at full speed. The pentium 3 system would display a broken black & white image at best, and on my current system... It outright SHUTS DOWN when trying to run any ROM. To be fair, the msdos version of this emulator always struck to me as unfinished even when working right; ingame menu is glitched, options menu displays at wrong text resolution, and so on.

I doubt theres any proper fix for these. Any other known difficult to run software or games?