1. Please create folder with name "asana_whmcs_addon"  with in  whmcspath/modules/addons/ and then upload extracted  .php  files to folder "asana_whmcs_addon".
2. Enter your assana API key that you get from your asana acoount setting in bottom left of your asana profile home and then click on APPS tab and then you will get Api Key link in to addon configuration screen.
3. Enter your license key as in addon configuration screen as well in license key field.