I've cleaned out the air lab and i've cleaned out the poison/slime lab, but when i finished the slime lab i didn't get the scepter for it and now i can't open any other doors.

The scepter is on the snake in the slime ( the poison lab? ) lab. Go back into the poison lab and hit Tab , it might be there. Otherwise it's a bug and then I imagine you must turn to the clua console.

This might have been no help at all.
Just doing my best [img]smile.gif[/img]

The slimes constantly regenerate, so just basically ignore them and attack the snake for the scepter. At this point, you should have two scepters (the air scepter as well). Read the notes that you find in each library room to figure out how to get the next scepter ;)