Hi Mark,
Have you considered Bromcom as a solution to your electronic registration? I have used this at my last school for around 2 1/2 years and at my current school for around the same period. The client is called Winfolder and it is made available via a shortcut to a shared install on a server... so, 1 install on the server and a single shortcut for all users.
We have some old machines and they run it a treat! The application itself is only 700K and is on the server anyway. The data that it sends back and forward is in bytes or maybe kb's at worst and it works really quickly. All of our staff have access to students home contact details, timetables, photographs and SEN information at the touch of a button (All this information is passed to Bromcom automatically from our SIMS server) We have very few staff who have access to SIMS.net as its a fat client and takes an age to install and upgrade.
We also see some benefit in terms of reliability as if the SIMS server is down for any reason we still have a copy of data in Bromcom and can still look up TT's and Students Attendance. All Attendance is also exported overnight to SIMS.net and so we have a fairly fault tolerant setup as an added bonus.
Our staff really picked up the client quickly as it is very intiutive and straightforward to use and we are really looking forward to using the behaviour module that we have recently purchased which complements the registers perfectly.
All of the guys at Bromcom are helpful and we get our problems resolved much quicker than calling the capita helpdesk.
Just my thoughts but I hope they are useful.
Kind Regards
Clark