"Skills" are free... they can't be sold. If someone else develops a skill it will be to control "their software product" they want to sell for DL to the WM100.
Skills may be currently free but that is changing. The cost of developing them is also not free.
Amazon charges to host these and that is based on the number of users of said skill.
I don't expect Authinx to charge for this, it wouldn't be in their best interest.
Over 90% of skills are developed not by the manufacture of a smart device nor do they control a device.
Some skills that are developed for a hardware come out months if not years prior to the manufacture releasing one.
I can think of at least three instances of this.
Unfortunately many skills created by individuals don't get updated.
One created by the Authinx's developer I would hope does.
And... realistically... I am sure (or at least hope) X10's business decisions aren't based on Internet forum posts.
This is not the reason for keeping discussions on topic!