you don't create drivers with URC. (unless you are using Total Control) you create devices that contain buttons that hold the codes.  you can import hex codes onto blank buttons using the Universal Browser, like musictoo mentioned, or you can learn in your own commands.  you can also drag codes from URC's database onto your buttons.

you then need to keep track of what project files contain the devices you created if you want to use these devices in another project.   these devices can be imported into other projects.

i believe urc already has crestron trigger commands in their database.

Look under AUX, then Crestron.