Why can't I click the checkbox when reviewing expenses from eBay?

The red checkmark is in the column titled "Create Expense Rule". When you click on this box, it will create a rule that assigns a general ledger account, description, and vendor to expenses automatically if the charge description matches. For the eBay sales, there is no charge description so we disabled the create expense rule option for these expenses.
 
So long story short, in order to review these expenses, you can click each line you want to review and then the "Mark Reviewed" button. Or you could also click the "Select All" button and then "Mark Reviewed".
 
Hope that helps -- also, here's a video that demonstrates what I'm talking about: Bank Integration for Expenses (timestamped the link to the spot that shows expense review).