This site is being deprecated.
Please see the official X‑Plane Support page for help.
The Dreamfoil AS350 was actually intended for use in X-Plane 10 - but the developer has created several patches to make it flyable in XP11. Check out this post (and especially the link posted by Daikan) which discusses the problems and a possible new workaround patch...
This site is no longer being actively maintained.