The short answer is no, although I have read where some things will work from FS9 to FSX. I haven't seen anything the other way around.
On BETA, I try to stay away from them for the most part. They can give you headeaches, you found that out.
Some programs for FS9 will be able to upgrade to FSX.
Think of computers this way. Progress. Sure it's all about money and more so it seems these days and customer support has gone downhill overall.
Look at television or automobiles or anything for that matter. New ideas, comforts, new technology, whatever names you can come up with, for the most part all these new products are better, but, you have to buy them. Autos, boats, airplanes, or computers. You either move up with new technology or stay with your older whatever ( like my Ford truck ) which may be dependable but out of date and throw some cash at it once in awhile to keep it going smoothly. Just my humble opinion for today.
Have a good one!!!!!