This directory is for the programmers. For client programming, you never need the PORT.H and LAYER.H. You only need the TRANSPRT.H, which replaces *both* TRANSPRT.H and DRIVERS.H from old STiK. Please try to compile your client with the new TRANSPRT.H, you should not need to change your source code. If the compiler throws about more errors or warnings, please tell me about it. Best : Send me the file the compiler did store the error and warnings, with an excerpt of your source code. PORT.H and LAYER.H are for STX programming only. You'll need PORT.H with TRANSPRT.H if you wanna write a port STX, like the SERIAL, MIDI, or ETHER. If you wanna start any such project, please contact me, I'll provide more info on it. LAYER.H together with TRANSPRT.H form the basis for a high level protocol STX. In future possibly there will be a Internet phone protocol STX. Again, contact me if you wanna start on a similar thing. These header files are written for use with Pure C. Other compilers might need slight adjustments. Try to #include the file 'portab.h' before the actual #include's for the other header files. If that still gives you problems with your compiler, contact me. Keep hacking ;-)