Please send us your screen name and screenshots at firstname.lastname@example.org so we could investigate your case and get back as soon as possible with the answer. (most of the cases following answer...
First player and First team to score prediction will be available from Knockout phase (Round of 16). Please see more information here: http://uclpredictor.uefa.com/match/rules
You can have one Joker that can be played for a single match to get double points for each Matchday.
Please find information about the pirzes in section: http://uclpredictor.uefa.com/match/prizes