Almost overlooked this one - I've now registered our restaurant facility for it.
We don't have the resources to try and reprogram our payment systems to handle this, especially for just 4 weeks during our quiet days. Thinking of just preparing a pile of A5 calculation sheets for restaurant staff to use, where they just enter in relevant info (number of covers, gross amount received, less: alcohol, tobacco, tips etc) and work through to get the comp amount to apply. Copy receipt could be attached and then all handed to the back office to process.
May try and dig out a couple of clipboards with calculators attached for staff to use...
Anybody got any better suggestions, or comments on anything I may have missed?