Oh well.
I honestly believed that, playing standard Acol, I can find the right bid more than half the time at the very least. But this sequence utterly stumped me. All playing weak two's:
Show one of my minors at the 4-level? 3NT with no spade guard (and lead coming through my partner)? WTF????
I passed, and, needless to say, the result was a mere -12 imps....
I think I'm in the wrong game....