One big issue is beta testers. Somehow you have to get users of the various Windows versions (95% of sales), as well as OS X and Mac OS 9 (3-4% of sales), to verify that the files work. To find out if there's a market, post images in the Poser Forum or Product Showcase Forum. If the object can be posed (moving parts), it increases the market to Poser users, who buy tremendous amounts of things daily.