Hello!
Could you compile a program with only the Linear Interpolation.vi and only some constants and indicator as input and output?
I tried on my PC and compile a simple VI containing only the Linear Interpolation.vi
Which Version of NI-RIO do you use?
Do you also placed the FPGA VI in library? If yes put out all FPGA VIs from the library and check that they aren't reentrant.
This could cause problems to the compiling of FPGA VI.
Try to create a new project with only a VI with the linear interpolation and check if it is compiled.
Best regards
Ken