[LAU] nanokontrol and go to start of session

[Kim Cascone]

I'm using Ardour 2.7.1 on Ubuntu and just hooked up my Korg nanokontrol 
control surface
I assigned the faders and buttons to the mixer faders and solo/mute buttons
with the ctrl+middle click
no problem
works like a charm

I then assigned the play and stop buttons
again no problem
it starts and stops the playback as expected

the problem:
when I assign the 'go to start of session' on the transport section to 
the return button on the nanokontrol it didn't work
ditto on the 'go to end of session' assign and usage

an 'operate controller now' box did come up
and when I pressed the 'rewind' button on the nano it disappeared
but neither the 'return' or 'end of session' buttons function when pushed

anyone know what I'm doing wrong here?