Here's one man's experience with this. It is possible to create a usable design... but only if you toss the provided materials and start from scratch. Neither supplier, Arrow or Nuvation provides enough information to create a useful design. The only thing that you can do with either vendor's material is replicate an Arrow demo. There are errors in the Nuvation website FPGA design and nothing except an FX3 image file to work with. There is only an FPGA .sof file from Arrow. Neither party will provide any support. Finally, I got a email address failure when trying to contact the Nuvation contact person who is also listed as a Cypress third party support person. Still, if you have a limited budget and lot's of time to work through the incorrect and poor documentation this is a limited but reasonable starting point to develop your own FPGA/FX3 interface.
Our company (Opal Kelly - http://www.opalkelly.com) is announcing our XEM6310 in another week. It is a Xilinx Spartan-6 device based on the FX3 and includes our popular FrontPanel SDK. We also have our ZEM4310 (a Cyclone IV device) in the lab and getting ready for beta customers. If you're interested in beta testing this, please send an email to firstname.lastname@example.org. We expect to announce production a little later this year.
I think you'll find our SDK a much better experience.
We have also developed a board with full software stack, which uses FX3:
You can find more information at : http://www.linera.com.tr/en/products-and-services/products/
FMU3-S6 series is a spartan-6 based board with USB3.0 support. It has an on-board DDR3, a programmable clock synthesizer, Flash, and a microSD card slot, all in a 65x50mm package.
FM-S6 series does not have an FX3 on-board, but it is smaller: (50x50mm) and is pin-compatible with FMU3-S6
We have reffered to one of your board in the "getting started with FX2LP" application note.
Application note can be found in the following location: