Right so here are the answer to your above queries
1) Yes if you joined the Network in December you will recieve your first payment at the end of February, though you will be able to see the amount that is owed to you at the end of January.
2) You can always track your estimated revenue both on YouTube and the Freedom dashboard, however daily information isn't available on the Freedom dashboard as this is updated at the end of every month and only gives details for the month not individual break downs
3) You don't need to check for invalid clicks, unless you get a notification either from YouTube, Adsense or Freedom about this assume everythign is fine
4) Freedom follows the same rules regarding ad revnue as everyone else this is worked out to be the cost per mille or CPM - basically the amount of revenue you earned based on 1,000 ad impressions