Play using dosbox with relatively low cycles, Quest games have this issue in common, on faster systems they look as if they ran at the proper speed, but some sequences were made too fast to be played.
For example, if You ever play SQ1 [SCI], You may see that the Sariens on the ship enter the screen before You have a chance to escape. Also, in the caves on Kerona, the acid animation is so fast, You cannot possibly pass it without getting killed.
Therefore i strongly recommend DosBOX and toying with the cycles, the lower, the better.
Good luck and have fun!:D

Exactly like Arteveld said. I think the shorcut to change the cycles is Alt or Ctrl + the F11/F12 keys or something like that.
However, in Space Quest 6, you may actually want to turn the cycles UP, cause the game runs a little slow by default.

Ctrl + the F11/F12 is right.;)
Can't help You with SQ6 though.
I'm more of a SQ1-3 guy, i finished those so many times i have it all in my head. :P
Curse the internetz for the insta-find walkthroughs, my knowledge of the SQ is useless!

When in the mall with the lasers, it also helps if you go to the in-game options screen and lower the speed there.
I think you only really need to do it for the floaty bit, everything else should be okay.
This (and the lower cycles) also helps fix a couple of things in Quest for Glory 3 and 4. They both use the same engine as SQIV, and so have similar speed issues.

This page contains patches that should fix all of your troubles. Especially the first patch, which fixes many bugs, including the timing errors, and even restores some deleted content.

It's funny even without patches I've never had issues with this scene. It's all in HOW you fly. You need to approach from the left side of the mall - fly up, then fly right, then fly down - exiting on the right side towards the arcade.
They will NOT hit you if you do not stop moving. This is at cycles of about 9000? Without patches it never gives me grief.

Just because You haven't encountered that problem, does not mean the problem does not exist. Quest games are known for their timer issues. I've played SQ4 back on a 486 [or even 386 i believe], and played the game a lot of times, through all the hardware upgrades [Pentiums and all]. And on 'newer' computers i had those issues, I had to play around with game speed and mo'slo, until DosBOX came out. Yet still, finding the right ammount of cycles is tricky.
I'll take SQ1 as an example, it has the same engine, and the same timer issues.
WIth cycles=3000 on core=dynamic, in the scene where you flee your ship, and pass a room with a few monitors showing a green Sarien face talking [the screen between the lift and the airlock entrance], the guards would shoot You when You're about halfway the screen. On cycles=4000 You'd get shot when You're about 3/4 of the screen. After playing that screen a few times, the solution was to use cycles=4000 and push game speed in the options to the max.
I bet it would be easier on another core setting though.
Anyhow, as an SQ player since 1992 or so, i can guarantee, times issues exist. ;)

I never said they didn't exist, it's just that in the 300 times I've played SQ4, - on computers ranging from 286 - 486 - pentium- pentium 3 - dosbox - I have never seen timer issues with SQ4. SQ1 SCi - yes of course. Terrible timer issues. QFG4 - unfinishable in some cases without patches.
But SQ4 I find the laser sequence is mostly due to not knowing where to fly. Just my own experience yes but I would gladly make a dosbox video if you guys would like? No patches, cycles up the ying yang. :) I'm not suggesting they don't exist, I merely suggest they are passable without patches.
I have tried the patches as well but I find the laser move just as quickly with than without.

Perhaps the phrase "It's all in HOW you fly" misguided me, sorry.;)
So we have similar experiences when it comes to Quests, but with different outcomes. I remember the timer issues with SQ4 mostly because, i had no problems on a 486, but friends with faster machines complained about them, and when i finally got a Pentium myself, i faced the same problems. I somehow managed to overcome them with the game speed slider [SQ1 required moslo], I guess one can walk around the timer by flying in a specific manner, but on the other hand a game is meant to be played, with gameplay being the players general concern, not the bugs.;)
So i think it would be great if the GOG's quests had the patches [and the sound setup utility mentioned in another thread!]. ;)
Isn't GOG all about the perfect game experience after all?:)
Sidenote: The timer patch in SQ1 does not help with the Sarien guards appearing too fast. It's all about the cycles and the speed slider. Kinda sad, wonder how/if GOG will fix that.;>

Yep. That's the bigger issue. You shouldn't have to do it "one way". Like I said I usually never notice because I guess I happen to get lucky and use the same path. Any sort of hesitation = death, which is kind of annoying for new players especially.
Should be noted also that you should ALWAYS use the fan patches anyway. Otherwise you have to lower the cycles to the point where mouse feedback and screen transitions are too bloody slow. With the patches you can raise them up a bit (except maybe Quest for Glory's combat of course, which is tough to balance)

It's funny on my modern system, with cycles at 10000 I'm getting shot at before I even step into the arena to fly... I set my game speed to maximum and set cycles to 2000, and I managed to fly up first, once I cleared the first screen it was a cake walk...

Is anyone able to fix this error now that the games use ScummVM instead of DOSbox? I am struggling with this. The guy starts shooting at me as soon as I walk into the zero gravity, there is no chance to get away.

This section is just bad I'd suggest just finding a savefile just after the section and using that.

Did you find a save file, or other way around this problem?