Is there an easy way to use Reggae and it's classes from within Arexx ?

Currently no. But well, adding ARexx interface to Reggae is very interesting idea and opens a lot of possibilities. I will definitely add ARexx port to multimedia.class, to allow Reggae to be used from ARexx. I only need to think well about the ARexx API, which level of Reggae API should be exposed to ARexx.