...not sure what snp picon looks like do you have a screen shot...
They are the same as what you see on cooltv but the difference is all the work that has to be done behind the scenes...
Channels on satellite can change transponder/frequency very often and when this happens it's given another Service reference number, A service reference number looks like, "1_0_1_18F6_7FD_2_11A0000_0_0_0".
So, for example, BBC One HD changes frequency, this means that the picon for BBC One HD will not work (due to change in service reference number from changing frequency). This means Rat has to then view details of the new BBC One HD location and get it's new service reference number.
Then Rat has to find the old service reference number for the BBC one HD picon and rename it so that it matches the new service reference number for new frequency/location of BBC One HD.
Now imagine doing this with all the channels available on 28.2. Sometimes there can be a lot of channels changing transponder in a day (due to moving to a new satellite - they're several for 28.2).
The difference with SNP (Service Named Picons) is that the picon filename is named same as the channel so in my example, "bbconehd". This means that if a channel(s) change frequency 100 times in a few months it makes no difference because the channel name has stayed the same (which is normally true).
Obviously, if a channel changes name (very rare these days) then picon wont work without renaming it to match the name of new channel.
Hope that helps briefly(!!!) explain difference