Hi Bernd,
Thank you! I have never seen one of these anywhere so it will be interesting to see how (well?) it works in the end.
Anyway, it is all done now and these are the parts:

At the top we see the main block with its nut and washer, below that to the left the little spring and the plunger, then the lock dog with screw. To the right we see the hub of the star wheel seen from back with the drillmarks for click stopping, its center and fastening screw, and finally to the far right the small stubs with lock nuts.
As said earlier, the stubs have one, two or three rings to easily see which one is which.
Screwing it all toghether it looks like this on the bench:

Quite compact I think. Although I could have used M5 for the stubs/pegs instead, that would have given me a bit better clearances.
Placing it on the lathe to check that all measurements was correct (and they were).

I choose to use an ordinary nut for locking the thing on the lathe as I can get a little more clamping force using a wrench to secure it and know it does not move when graduating. The idea with the click stops work although they are a bit rough at the moment and really needs to be run in.
A final check with both saddle stops shows that there is a little difference in terms of how far from the bedway the centerline of the two stops are. This is calcualted as the final item - the micrometer stop - is not made yet and it will be placed on the saddle so that it gives a stop face for both clamp-on stops.

Fun little project this, and so useful at the end!
BR
/Peter