SITES similarities with LEED Online?

Here's how it was set up for my projects.  They were a couple years ago, so it might have changed since then:

Once you register, your project will have a 'Project Resources' tab on sitesonline.usgbc.org where blank versions of all worksheets and sample letters will be, but that, and paying for reviews, is about all you'll use that website for.  There are no credit forms.  You'll be invited to a shared Dropbox folder for the project, which will have an instructions document.  One person on your team can edit the files in the folder, and they can invite others to view what's in it.  You will create a subfolder for preliminary review, and sub-subfolders for each credit you're pursuing.  In that folder you'll upload a credit narrative (I created a blank narrative with a place for the credit name at the top, and copy/pasted it into all credit folders) and any backup documentation, including any worksheets or letters that you've completed.  Once you're ready for the project to be reviewed, you'll email them.  It's pretty simple and straightforward.

FYI - I recently registered a SITES project, and the process hasn't changed.

If I remember correctly, they told us we can just use our best judgement to determine which credits to submit with design review.