I think I found the error log. This is what It has for my last attempt to restore. It looks like it is timing out and then hanging on the browser.
1 POST /moodle/backup/restore.php - 1 Connection_Dropped DefaultAppPool
1 GET /moodle/login/ - 1 Connection_Dropped DefaultAppPool
1 GET /moodle/login/ - 1 Connection_Abandoned_By_ReqQueue DefaultAppPool
1 POST /moodle/backup/restore.php - 1 Connection_Dropped DefaultAppPool
1 GET /moodle/login/ - 1 Connection_Dropped DefaultAppPool