Agreed with @Christiane_Rode ! How (and also to what level, i.e., do you want this for all programs/just selected programs) you're planning to use the info in SFDC should drive how you pass the data over to SFDC.
Here are a couple of additional resources that might help:
Marketo Success Series: Email Programs
Marketo Success Series: Channel Building
As mentioned above, next time, you'll need to create a trigger smart campaign that progresses people through the campaign based on certain actions, and you'll want to do this for any status in your program (Opened, Clicked, Unsubscribed, etc.). If your instance is set to have bot activity logged but not filtered, you'll want to be sure to exclude bot activity in the trigger, just as a precaution.
For this time around, you could create a batch campaign that would run on similar actions (instead of Opens email, the trigger would be Opened email) ... with the same caveat that you'll want to make sure that bot activity is set to false. Depending on when you sent your email, you could also create the trigger campaigns to catch anyone who hasn't engaged just yet -- but this might not be moot if the email was sent a while ago.
Thanks!