Fair enough, I'll stay away from stop leak products.
When I first noticed the leak I took a look @ the pan & drain plugs on it and the converter and didn't see anything.. guess I'll check again.

I did find it really strange that it wouldn't leak while running but would overnight if it were a seal on a rotating part.

Honestly, this trans shifts well... but if it's gotta come out for any reason a manual is going back in its place, Simply for the fact that the idle in drive @ stop lights is so much rougher than that of my stick shift 240D.