Please try again, e.g. with MacOS 7.5.3 and drag the Quicktime Extension from inside the Golden_Gate.iso onto the System folder. To do that, you have to boot Basilisk II from another volume.
With the Quicktime Extension from the iso the game seems to be playable.
Animations are not as smooth as with SheepShaver, but working at least.
In case you don´t have a bootable 7.5.3 image, you may try this one:
http://macintoshgarden.org/apps/macos-753-emulatorsPlease note that mrdav updated the Golden_Gate.iso.sit.
It may be wise to download the recent file - unless you do have the original game, that is.

If you should have the original game, please consider adding the manual to the page at Macintoshgarden.