G'Day Chris!
Aligning to the SCP can take a bit of learning, and then it actually takes a bit of time to do usually. For precise stuff, like astrophotography you will need to learn to "drift align" i.e. make adjustments to the alignment of the scope based on the drift that you observe in the eyepiece. You're seeing that drift already.
For starters though, try not to worry too much about the drift. For visual observing a bit of drift can be tolerated and for a while you'll need to tolerate it until you get the hang of alignment.
Something about the dec slow motion control doesn't sound good though.
If there's no-one handy who can have a look at it, I'd agree - take it back and get at least some advice or tuition from the shop.
Al.