The UDFs are "Functions", and if you wanted to you could copy all of them you wanted to use into a single file and then at the top of the file you would call the "function" you want to call and supply the required parameters for it.

You can do calls to the functions based on criteria that you also setup. ie. IF ELSE type conditional checks or INGROUP type checks so that you only call a function if the logon meets your specified criteria.