The current PC,Mac,PC/Mac choice dates back to the early days of Poser3 where it was a significant problem - remember, it first took some time until the how-to PDF was first posted, even longer time until Budgie released his legendary AppleScripts, and much more time until I did my initial 0.5 converter... Today it is thankfully obsolete (except for the Utilities slot), but it's probably hard now to change anything. A new scheme could be: - PC ready (zipped PC library files) - Mac ready (stuffed Mac library files) - PC/Mac (hybrid formats like textures, ready to use on both platforms) - PC only (compiled tools) - Mac only (compiled tools) However, it would terribly difficult to change all the old settings, because there is no default rule for it, so it's probably best to leave it as it is (and to tell Mac people occasionally that they don't have to be afraid of the "PC only" mark... :-)