1. I have checked main color issue on our demo site. It still works. You can go to Traveler Setting -> Styling Options -> General -> Main Color to set main color. Please check it again.
You can refer our document to more details.
2. To use TravelPayout Whitelable function you need to setup a subdomain on your server and do some configuration in Traveler Setting. After setup complete success, when you search it will auto redirect to your subdomain. You can refer our document to more details.
3. I cannot access to your dashboard so i cannot check it. To create new search tab you can refer our document to more details.