There was a time when Filter Forge (FF) worked as a plugin for Xara Live Effects.

I tried with FF7 when it was offered out for free and decided to buy into v11.

I have found that both versions seems to work fine as plugins with XPro+ v21.8.

There was a time when this was important as you could apply a number of FF filters.
Today, it is just as slick in that you can use FF as a stand-alone and simply Copy & Paste the FF output back to itself and apply another filter.

Either approach works.

Acorn