OK guys i got the touch probe working (ish)

The bit touches the ali plate - stops and backs off
comes down again slower - stops

but rather than reset above it drives the tool down!!

for the purpose of the video - "PLEASE NOTE: No innocent tools were hurt in the making of this video. collet is loose and the tool is wounded volunteer" the thud at the end is the escape key being pressed.

http://youtu.be/6pdbWh9RMbc