> drag and drop pane separation: result in outputing escape charcters in
> buffer (ex: [<0;133;27m), error:  Wrong type argument: number-or-marker-p,
> nil

Hmm... I don't see this behavior.  I was able to get
a "number-or-marker-p, nil" error in "screen" and installed a fix
for that.
Can you try the latest trunk?  If the problem is still present, can you
give a precise recipe (ideally under screen or tmux rather than
directly in Terminal.all).


        Stefan