I'm inclined to agree with you about ASCOM Neil. What it's actually doing is buried too deep. I'd wonder about iOptron in terms of their method of aligning especially in unfavourable conditions, if you go that far – it swing back and forth between 2 stars. Celestron like the scope pointing at the meridian. Meads horizontal and pointing north.
I use a spirit level and a compass. It's surprising how accurate that can be. What's wrong with Meade's protocol. It's compatible with just about everything and is in all of the scope manuals.
A couple you may not be aware of and both pretty powerful.
These nuts use x m l and are talking about thin clients but there is some use of a 'pi around. The other problem is that the insist people run bleeding edge Linux distro releases.
http://indilib.org/
This one is a mix and graphics are handled by a tablet. Lot's of reading on this link. The code is on sourceforge.
http://www.cloudynights.com/topic/385710-piastrohub-raspberrypi-for-autoguidingdslrgoto/
John
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