Hey
1) Are the contents of the FSX directory transferrable to corresponding folders in Prepar3d?
Generally yes. You have to be careful to not forget any special gauges etc, but the C172 for example works as expected. But you will have problems with planes that have FS9 textures - it's the stuff that Steves DX10 fixer took care of with FSX. There is no guarantee.
2) Granted it is expensive and takes a great deal of CPU and computer space. v1.4 is Directx 9c compliant. Yet v2 and soon v2.5 are only Directx 11 functional.
You can buy the academic version. The distinction between professional and academic version is, well, academic.
P3D 2.x is actually much easier on the CPU but harder on the GPU.
3) My system is compliant to recommended settings of V2+, except for Dx11. It us a Dx9c graphics system.
Then forget it. You need a DX11 capable GPU because without tesselation it's not worth it to switch to P3D 2.x
So is v2+ worth further exploration or should my focus be upon v1.4?
Advice and comments are most welcome.
I think if FSX is working well for you right now you don't have much to gain by switching to P3D but a lot of potential headaches coming your way. P3D 2.5 does look better than FSX but not THAT much better. Eventually Lockheed Martin will have to go 64 bits and then of course also switch to DX12. That, I would say, is the time to definitely switch over.
I run P3D 2.5, never tried 1.4. It's worth it for me because I run it on a laptop and with my GPU / CPU power and heat dissipation P3D works better.