The biggest red flag would be not providing solid evidence that you and your partner have lived together for at least one full year, prior to submitting the application.
Things that can prove this would be:
joint lease or rental agreement, utility bills showing both names, joint cell plan, joint bank account(s), mail addressed to each of you that has been delivered to the same address during that year (not just a piece of mail from last week), etc.
You have to prove two things to CIC:
1. That you and your partner are in a genuine, loving `marriage-like' relationship.
2. That you have lived together for at least one year to be deemed Common-Law.
