Hope I'm not the only person that finds this somewhat unsatisfactory.
1. It is true that when offering a free domain for a product that will be purchased with certain payment terms, one can select which TLDs to offer by holding down the CTRL key when clicking the options to select more than one.
However, when you have over 50 TLDs, it becomes impossible especially when you want the page to arranged alphabetically.
The right option would have been to make it look the way the domains at Product Bundle normally appear. That is, using a check-boxes preferably a pop up.
2. When customers search for a domain and the result list the result and perhaps ... suggestions. The right thing should be for the "Continue" button to be near the result on top and also on the bottom should they scroll down.
I have attached images to show an example of what I have in mind.
I know the WHMCS will take these into consideration since they have proven time and time again, that they take our input seriously.