Using 3.168 I no longer have the use of 2 finger tip taps on Magic trackpad
I don't think there has been a change to these. What kind of actions have you assigned? Have you already tried to restart your machine?
Is BTT enabled? (Click menubar icon to see)
I assigned the (Left) tip tap to open a finder window, and the (Right) tip tap to (Command W - Close) any window. These were 2 of my most used shortcuts. I have re-booted, Disk Utility in recovery mode etc. but no luck...
Do your other gestures still work?
Yes, all others work
Unfortunately I can't reproduce the issue.
Maybe open the preferences and click in the menubar => help => export diagnostic debug information. Then send the resulting BetterTouchToolDebug folder from your Desktop to email@example.com. This might help me see what's going on.