Over on the left, in the menu, under "Domain Licenses" you will see a link for either "Leased Licenses" or "Lifetime Licenses".
If you purchased a one-time license, your lifetime will appear under "Lifetime Licenses". If you pay monthly, your license will appear under "Leased Licenses". Click the one that applies to you (or just click both until you see your domain).
Once you see your domain license listed, delete it. This will automatically credit your account's license inventory --- freeing up the license to be used for something else. Then simply click the Generate New License button at the top right and create a new license for the domain you want to "transfer" the license to.
You would use the Custom Code object. To do this, drag the 'Custom Code' object to the grid in the Page Editor. You will create a New File and paste your code into the the text area. Save the file and your code will appear on your page. You can also use the same code on other pages by dropping the already saved custom code object onto another page's grid.
First login to your sohoadmin panel. Then click on the Template Manager module. Here you can choose a new template from the dropdown list of templates. Simply select one that you like, then click the green button labeled "Use Template".