I consider myself a developer rather than a designer. Many years ago I produced some aircraft for CFS1, CFS2 & FS2002 but that's as far as I go.
Oh, I forgot: the plane that I would like to convert is the Boulton-Paul P-82 Defiant, originally once designed by Jed (I wish I knew who he was), which flies ok in CFS2 and FS9, though it's an mdl610.
I assume you mean this one.
http://simviation.com/1/search?submit=1&keywords=Boulton+Paul+Defiant&categoryId=83I've checked it out & from what I can make out it was produced with an early version of FS Design Studio (FSDS 1.6?). Animation was added with a separate software named Aircraft Animator. I'm not familiar with the latest conversion techniques but I'd be surprised if it's fully compatible with FS9 & I doubt it's possible to convert this model for use in FSX.