If you have blockers, you should just state the blockers, and then if you need to communicate with your mentor, do so on your project threads.
This is because I go and look for four posts from our selected contributors each Friday. The other bit is that if you are communicating, your mentor already knows. The reason for the blockers question is to allow me to track your project progress in the event your mentor shares to me that you are not progressing since it is used as a factor in what I suggest to deal with the lack of progress.
To reiterate: You should be talking with your mentor if you are struggling, do not spin your gears and struggle alone, ask your mentor for help. I want you all you be successful. It looks great for you and for us as well.