These are all just suggestions, not criticisms of the systems that people worked hard on.
Some way of controls contacting each other that was offline (IE, not phone calls, and not facebook) would have been great. A standard email account that all the control computers were logged into, something like that. So that people coming on shift would be able to see what had gone on, and any messages.
From what I understand (not sure if this is right, but it's what I heard) the bag drops were scanned into one place as riders. This could be avoided in future by having a prefix (on the barcode, no need for it to be visible) so instead of just the rider number on the barcode "MM20" it would scan in as "BAGMM20". This could be dealt with easily by the scanning software, and avoid scanning bags as riders.
Quite often the scan would not "press enter" when you scanned a bar code, and sometimes there was a lag between scanning and anything showing up on the screen. This would leave you wondering if it scanned, if you had to press enter, or if you had to scan it again. Showing what's been scanned as soon as it's been scanned (showing something like "Fetching data for MM20" as soon as the scan is done), maybe a timeout on the scanning field (1/2 a second with no entry should press enter automatically for example) would work around these problems.
As for the rider numbers. Please don't use I, II, l, ll. A tired volunteer trying to quickly spot the difference between II1 and I11 would have to do more mental work than necessary.