- extract the .rcUI files into the RapidComposer Settings folder:
on Windows: C:\Users\<user name>\AppData\Roaming\RapidComposer\SettingsV2
on OS X: ~/Documents/RapidComposer/SettingsV2
- Click on the 'Settings' and 'Miscellaneous' tabs, and scroll to 'User Interface'/Theme in the list.
- Select 'Import' from the Theme menu, and open the .rcUI file that you wish to use.