Try this. It's not the easiest, but it does work:
1. Create a new project (basic02 or as applicable). 2. Place any headers that are needed to build the project into the directory with your other source files (the project directory). THIS STEP IS THE KEY. Ensure you place all needed files in the project directory. (In this case: basic02.cc, string6.cc, string6.h). The way you determine this is by checking each file to see which headers are required 3. Insert into your project the source file(s) to be compiled. In this case basic02.cc and string6.cc.(the header file(s) do(es) not get compiled). To do this, choose Project>Add to Project>Files... 4. One note of caution: You must ensure that your #include statements tell the compiler where to look "" means project directory, <> means default include directory.
Let me know if you have any other questions... or if you figure out a better way of doing this.