Man, I have had the worst luck with the latest games from GoG.
Interstate 76: Cant even really play it. Even with some of the workarounds, it is bad.
Bloodrayne: Stupid spider gets stuck on the tree, and wont become unstuck (even on reloading).
Bloodrayne 2: This one isnt gog's fault (if any of them are even), but what crappy handling this game has. Seems to be almost unplayable with mouse/keyboard (the seperate camera is horrible).
Advent Rising: I cant even steer. Crash into the tub x10000. Wont even try the game anymore.
So, of the 5 games I have bought in the last few weeks, 4 are unplayable, and the last 1 (Psychonauts) I havent tried yet.
Is there a way to gift some of the games to someone else?

Nope, once you've bought them, you can't gift your "copy" away.
I share your frustration. Interstate 76 ran fine on my PC for a while, but at one mission, it kept crashing so regularly, I gave up playing anymore.
As much as GOG's still my choice as a digital distribution platform, I'm probably going to abstain from buying anymore GOGs until there's an indication that GOG's still actively working to make these games work properly.

You can't gift games you already own to other people for obvious reasons.
What kind of computer do you have? Specs and whatnot?

Well, my main gaming rig is:
Core 2 Duo E8600 3.33ghz
GTX280
8800gt phys-x
4gb memory
X-FI sound
XP x64
22" 120hz monitor (1680x1050)
I have a old 98 machine I keep around for Recoil, Tomb Raider 1, and Carmageddon.
Is there a way to install the GoG games on the 98 machine?

I wish they did a better job with properly placing the patches for Gabriel Knight 2. :(

Blood rayne sounds like one of those one off odd bugs that don't happen most of the time.
Advent rising was a buggy game before gog got their hands on it also.
Install and play psychonauts. It works really well with mouse and keyboard and it shouldn't have any problems. That and its one of the best games on this site, so should at least cheer you up a bit after all that bad luck.

Interstate is buggy, no question. I'm dissapointed by GOG on that one. And they've only made one post in that forum.
Bloodrayne games are console ports...like many action games on PC, you're intended to use a controller.
I have about 60 games here though and have barely run into any issues. I recall one and that's the developer's fault. Others GOG or the community has helped me with. So don't give up or let this taint your impression. I would get on their case about Interstate though.
Edit: yeah, play Psychonauts. :)
What do you mean?

lol way to troll 'em
the last level of psychonauts will make you want to rip out your spinal cord and use it to play folk tunes on the worlds smallest violin.

Well, I have 15 games from GoG, and these are 4/15 that have been bad.
I branched out from my usual games recently (I usually only play real first/3rd person shooters.
But since playing Borderlands and Mirror's Edge, I have been trying new genres.
I have to say, I should have stuck with fps games.
:(
Braid has me all mad (just cause I am dumb, and cant figure out puzzles, :P).
Red Faction Gorrilla is kind of entertaining, only because you can destroy stuff.
stalker was just a big piece of poop.
Prince series is horrendous.
Etc etc etc
So, I decided to take a chance and play some games I would not normally touch.
I dont mind if they suck too much, but when they are buggy is what gets me going.
They arent that expensive, and it gives gog money to keep going, and maybe get a game I want on here.

I suspect GOG have had to rush a few releases because of the whole Activision thing. They've been known to make amends for initial bugs before, even those that are not theirs, such as the helicopter boss crash bug in Duke Nukem: Manhattan Project.
Releasing several older multi-disc FMV games, as well as Interstate '76 which has been notorious for being ridiculously hard to get working properly on newer systems for a while, in such a short time-span, has probably affected the overall test and QA time available for each release and thus more users than normal have problems with them.

Do you mean the very start of the game when you have to dock with the space station? When I first installed the game and tried it out, it frustrated me to no end when the camera would immediately start rotating around while I tried to control the ship with the WASD keys and mouse. I shut down the game and checked the forums, finding the widscreen edit which I decided to enable in the config settings. When I was editing the config settings I noticed that the joystick was set to 'True' (or 'on'). Changing it to 'False' ('off') stopped the camera from panning around and allowed me to steer properly.
Advent Rising is quite buggy though; it's shut down on me several times during my playthough. It's a pretty good game though, so while the shutdowns are annoying I just restart the game and start playing again from the last save.

Oooh please try to love Mirror's Edge. :)
I figured that too. But it's the difference between annoying/occasional bugs for some people and game breaking bugs for pretty much everyone. They should've put Interstate off until it was ready, or if they couldnt get it working properly, not released it at all. I feel like I have to check the forums for bugs before buying now...before I didn't even think about it.

This might be part of the reason as it was more of an experiment on MS part and AFAIK never received proper support from anyone.
Couple things you could always try in case of problems are turning down/off graphics or sound acceleration (from dxdiag) and trying to run a game with one core. Unfortunatly, having not played any of the games you mention, I can't give game specific advice.

i'm not sure anything supports XP64. ;-)
but then again, interstate 76 doesn't support anything.
Do you mean the Prince of Persia series? Cos you couldn't possibly dislike that...

To be fair, that is true regardless of whether you are using a mouse/keyboard or a gamepad :p