OK. Here we go:
To select a devkit when you are setting up a scratchbox target via sb-menu, the target MUST NOT BE in the list for it to be selected (Pressing Enter should remove it from the list for it to be active!!!).
And I had to spend days wondering why is the cpu-transparency list empty even though the cputransp devkit is there in the devkits selection menu!
/me is really pissed off.