To add or change your company logo, head to the "Manage Access" page that is accessed from your SimTutor Dashboard.
Along the top, go to the "Accounts" tab.
From here, you can upload/change your logos by clicking in the middle of those two boxes at the right.
The "Main Logo" shows on the Dashboard of the users in your account.
The "Small Logo" shows at the top of each simulation within your account.
Be sure to click save when done!