x86 and x64 Compiling issue

Hello everybody. I posted an issue a few days back, and unfortunately another one made its appearance.

My project built smoothly (with warnings on the FluidProp module, my supervisor used the module before and told me that I should expect them) under the Win32 platform but as I ran it, it wouldn't go past one a basic instruction of opening and reading a file as you can see on this extract of my program.

Program gas1sv3

use FluidProp

character(18) :: namefile1="Input.DAT"
INTEGER :: iop

open(unit=20,iostat=iop,file=namefile1,action="read")
      if (iop/=0) then
      write(*,'(a)') "ERROR: unable to open file ",namefile1
      pause
      stop
      end if

	READ(20,*) GT !PLANT LAYOUT (GT/CC)
	READ(20,*) CONFIGURATION ! CYCLE (BASELINE/ADVANCED)
	READ(20,*) WFFIDP !WORKING FLUID SELECTOR
	READ(20,*) FFDP !FUEL SELECTOR (DP)
	READ(20,*) NDP  !SHAFT SPEED IN RPM
	READ(20,*) W1DP !COMPRESSOR INLET MASS FLOW
	READ(20,*) P1DP !AMBIENT PRESSURE
	READ(20,*) T1DP !AMBIENT TEMPERATURE
      READ(20,*) INTPLOSSDP  !TOTAL PRESSURE LOSS IN INTAKE
	READ(20,*) M2DP !MACH NUMBER AT COMPRESSOR 1 ENTRY
	READ(20,*) CPOLYDP  !COMPRESSOR EFFICIENCY
	READ(20,*) CPRDP  !COMPRESSOR PRESSURE RATIO
	READ(20,*) CMapNb  !COMPRESSOR MAP NUMBER
close(20)

end program gas1sv3

My initial reaction was that the issue was that I ran the build under the Win32 platform on a 64bits proc, so naturally, I tried to build the project on the x64 platform. The build showed errors on the files of the FluidProp module.

FluidProp is a thermodynamic library that's free to use (http://www.asimptote.nl/software/fluidprop/fluidprop-details) and they provide files (see attached)  for you to call fluid properties in your program. When you install FluidProp they install both x64 and x86 versions. At that point I was even more conforted in the fact that the issue was the build under Win32 and not x64.

But as I ran the sample client for FluidProp (see attached) under the x64 platform, I get 10 errors (see buildLog) all of them being "the type of the actual argument differs from the type of the dummy argument" and the client cannot be ran. BUT when the sample client is ran under the Win32 platform it runs just fine.

So, I am kind of confused right now... Why won't my program open and read my file ? Is it because I should run all of the program in x64 -which I can't do for now as FluidProp shows errors- ? Or is it because I messed up in my initial program because FluidProp runs fine when compiled under Win32 ?