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Unfortunately, even the patched version of the game has some bugs that can become problematic. This is especially true of the hardware-accelerated renderer, which is rather unstable even on a vintage PC. It is possible to use the DxWnd loader to make the game behave better on modern systems, but this does not solve all of the bugs listed here. DxWnd includes a Mageslayer configuration that you can load and tweak to your liking.

Note also that the installer is 16-bit and does not work on 64-bit Windows systems. Rather than installing, simply copy the "mageslay" directory from the CD to your desired location on your hard disk and rename it if desired.

Bug Additional info
Lifts get stuck This is a particularly frequent problem with the platform that raises after defeating the Rat Lord, so it's a good idea to get on that one ASAP when the Rat Lord is defeated. Other platforms can also be affected, though. Uncertain of the cause.
Platform follows incorrect path In World 3-2 (Movements of the Earth), the platform over the lava leading to the key can glitch out and move somewhere it shouldn't. This can make the level impossible to finish. Uncertain if it's the same base problem as the stuck lift bug or a discrete issue.
Accessing secret levels from a boss level breaks progression If the player enters a secret level from a boss level, then after defeating the boss and returning to the vault, the next exit will send them back to the secret exit in the boss level rather than to the next world, effectively locking the game progression in an infinite loop. This affects two of the secret levels (Maze of the Arborite and Lore Thrall's Dream). Currently the only known workaround is to avoid visiting these levels.
Loading saves from a different session when a game is in progress can result in corruption When this happens, the console will report "item service run for unknown race 0" and the player's inventory will be messed up, sometimes including invalid items. Dying after this may either fix things or corrupt the game further.
Question mark gibs from certain enemies Sometimes when you kill one of the magnetic robot enemies in the Desert Keep world, they'll leave a question mark icon on the floor. This doesn't appear to harm the game any when it happens, it just looks odd.
Exception c0000005 crash when leaving The Vault This is a memory corruption error of some sort and appears to be linked to the Direct3D renderer. If you have problems with this, always switch to the software renderer when traveling to/from The Vault. You can switch back to hardware rendering afterwards if you are determined to use it anyway; the bug only seems to affect The Vault.