A new release (v3.3-110) version from SmartMount is available.
Starting with the alpha 106 the Action Button is a separate Addon. The preferred way of using it are still the key bindings or the macro. I maintain the Action Button only very roughly – but if you want to take over, just let me know.

Infos, Bugs and more: SmartMount / SmartMount Action Button

Preferred way of installing: via the Curse Client