Regarding the 2 finger pan/zoom, I can only say it is working for me, in Photoshop. Not so much elsewhere (e.g. Corel Painter... it sort of wants to work, shows the red zoom + or - icon, or the pan tool, but doesn't reliably change the view. This was true after defining Astropad shortcuts for Zoom +/- same as Photoshop).
I have a feeling the magic gestures are going to need to be definable on a per application basis. I was playing around in Painter last night and defined 3 finger + pencil tap as Modifier Cmd + Option, this brings up the onscreen brush size adjuster in Painter. However, the similar but different onscreen brush adjuster in Photoshop is Ctrl + Option, so ideally, I'd like to be able to set this accordingly per app.
One other thing that is still a little mysterious to me (and may be a factor if you aren't getting finger pinch zoom), is the popup about using "finger mode". While checking some shortcuts in Safari via Astropad, I realized that I could get Safari itself to scroll with 2 fingers, but that after the finger mode popup. The next time I touched with the Pencil it turned finger mode off and said Magic Gestures were available again. So for me, it looks like it is doing the right thing, although the exact logic behind it is a little unclear. For example, normally, in Photoshop using the pencil, if I try to use a finger tap it shows the red finger press but it has an X in it and doesn't do anything, That's not a problem, just not sure what causes what to happen here yet.
Anyway, I mention it in case it might have some bearing on your issue of not getting pinch zoom to work.