I had the same problem since PR 1.2
(But I do not have much experience with gtk,
so this may be in fact another problem or just my fault).
I tried to detach the selector from the liststore
by setting the current model to NULL, and then clear the
liststore.
But this gives some warning from the touch selector
(invalid iterator). Finally I got it working by deselecting
any touch selector row. (set selected row to -1).

Maybe this helps

nicolai