Kevin,
As far as setting FxSound as the Default Communications Device, my guess is that if you do so, it sets FxSound as both the Default Device ànd the Default Communications Device simultaneously, but, shows it named only as Default Device in the sound settings.
Your idea has been suggested before, but unfortunately, that’s not how FxSound works, and it could simply never work under that condition no matter what you or anyone else tried.
The basic axiom is that in order for FxSound to be able to process any audio, it must always be set as the primary, Default Device; and if this condition is not met, then no audio can or will be processed by the driver.