Yes, you do need to create an account. However, you do not need to provide much information about yourself, your name and e-mail address are sufficient to be able to fully participate in the hiring process.
For each listing, there is a shoutbox giving you the opportunity to post messages concerning the general hiring process. Each application has its own comment section giving you a way to let the other members know what you think of this particular applicant. All these comments are only accessible by the other selection committee members of this listing.
If the listing administrator has decided to activate a rating widget, you see it on the individual applications. You can then rate the the applications individually. After doing this, your ratings are not yet confirmed, meaning that the other members cannot see it yet and it is not included in the average rating. If you are happy with your ratings, just go to the application overview and confirm your ratings by clicking on the "confirm" link. Notice that the color of the rating gives you a quick indication whether the rating is confirmed or not.
If the listing administrator wants you to look at certain applications more carefully, he/she assigns them to you. You can see this by looking at the last column by finding a bar in your color (for your color check the activity page of the listing) or hovering over the bars. You are also able to filter the applications to show only those assigned to you.
The listing administrator is able to hide applications if they are currently not of interest. This puts the applications at the very end of the overview and makes them appear grayed out. You can still access all information, it is just a visual clue.
You have the possibility to export individual applications as combined PDF document or multiple applications as a zip of these documents. Please make sure that you secure these files properly.
This is a way to attach applications to the top of the list for easier access. This only affects your own overview, it has nothing to do with rating and the other members are not able to see which applications you moved to the top.