Hi Neil
Stainless can be a bit tough but is easy enough if you just take it softly, check your finished hole dia to make sure it is in spec (Zeus machinist handbook) and only rotate the tap clockwise(assuming right hand thread) about a 90deg then back off to break the chips continue until hole finished. as you have described the metal creaking it is obvious that your lube isn't up to the job, i use a product called trefolex it's a paste and will stick to the tap and i have not had any problems tapping stainless.
softly softly catch'y monkey.
Regards
Mike