I don't think it's supposed to be like that, no. I'll have to examine the code more thoroughly at those points to see what's going on. I'm a little surprised that you managed to get to the porn store and have sex with Rouge without also getting to the point where Cream will get naked as well, though, seeing as how you have to go through a couple of encounters with Amy and Sally via the park, fountain, and over the phone to get the map to the porn shop first...
Anyway -- once you start getting those stats like touch, exposure, happiness, etc. above 10 or so, they really don't have many other effects in the game. Your RWC (Relationship With Cream) score becomes the primary factor in what she will or won't be comfortable doing... so it's possible, I suppose, that
that is what you're doing wrong; you're focusing too much on getting those other stats up, but not doing enough to actually get your RWC high enough?
Keep in mind, too, that this is still a "zero-point-X" beta version, adapted from a long-abandoned Flash game that was itself incomplete, so there's probably quite a few issues like this where things don't quite work as expected because Avalon never implemented them (or only implemented them half-way), and neither Proto, FuzzyBunny, or now myself have gotten down into that part of the code to straighten it out yet. Like it says in the in-game FAQ and tutorial, the game is playable, but it's still very much in an incomplete state, so there
are going to be paths that can't be followed, achievements that can't actually be achieved, missing guardrails on the hairpin turns, and spots on the map marked "Here Be Dragons" that will swallow you without a trace if you stumble into them.