I got King's Quest 8 and got it all installed, but whenever I play it it crashs. The furthest I've been able to actually get into the game is after clicking the 'New game' option and the load bar gets 1/3rd the way. I've uninstalled and reinstalled it, and that's the only thing I can think of. Any one run into this?

Here's a few things you can try:
*Making sure the install directory (Use the offline installer instead of galaxy) is a one with few characters. e.g c:\games\kqviii (Some old games don't do well in GOG's default Program Files (x86) directory, KQ8 seems to be one of them)
*Run King's Quest VIII in Win95 compatibility mode
*Try updating the nglide wrapper or try dgVoodoo2

EDIT: After installing make sure you switch the graphics mode from directdraw to 3dfx 800x600!

If none of these work, try looking in the King's Quest Forum. https://www.gog.com/forum/kings_quest_series#1611698630

Note: For me, installing in another directory and setting the game to launch in Win95 compatibility mode is all I needed. I later updated to dgVoodoo2 (nglide 2.10 didn't like this game on my machine), but it worked fine without that change.

So functioning as designed then?

This is the problem with trying to run games from that black box era of graphical APIs.

If you'd like to attempt to find more specific help, I'm sure there's people willing and able in the King's Quest game subforum.