Are LIB files made with Intel/DEC Fortran 100% compatible...

...with FTN95 ?

100%? Unknown in computing circles!

However, your libraries may well work with FTN95.

1. They probably use STDCALL and this is not the default for FTN95 (see IMPORT_LIB on the FTN95 command line and Reference Properties in Plato)

2. Passing character variables can be very tricky.

Thanks Paul, I missed import_lib and had sometimes unexplainable problems for years with some old libraries in some specific cases. Now it works with all parameters fine

Forgot to ask. How about other compiler vendors libraries for Windows in general. Did compiler developers followed some sort of standard to make libraries compatible across the platform? Specifically, are chances good to link Lahey/Absoft/gfortran libraries with FTN95?

I think that most have followed the Microsoft lead and adopted the STDCALL protocol. FTN95 is the exception where STDCALL is not the default.