Gabriel,
If you haven't found a way yourself yet, you might try something like this:
Code:
property lastRunDate : date "1/1/1"
property persistentCounter : 0
set currentDate to current date
if (currentDate > lastRunDate + 7 * days) then
log "do this"
else if (short date string of currentDate is short date string of lastRunDate) then
log "do that"
else
log "do that other"
end if
set lastRunDate to currentDate
set persistentCounter to persistentCounter + 1
HTH,
Ciao,
Roeland.