There is smaller number of SW, which works not in emulators.
Usual reasons are: tricky antihacker code which is not 100% correct emulated. Examples: Warp, Blood Money .
Very hard to fix. Usually in protetion, so cracks may work.
Game bugs, which fail on STE and therefore Steem too (STE only emul.) . Examples: Grand Monster Slam, Hyperforce.
Easy to fix, patch in Steem.
Some other case of not perfect emulation, combined with unusual code. Example: Microprose Golf. It crashes in Steem, Saint, Hatari during intro.
The reason is not 100% accurate MFP emulation.
Here may DL STX images with patches, MSA images deprotected, fixed for emulators and hard disk runnable v. too :
http://atari.8bitchip.info/ASTGA/M/mpgolf.php