The #include statement can only be run as part of a program. If you try to run an #include statement from the command-line or using "run selected text" (using F4 or the context menu) from an editor window, it will return a syntax error.
However, the two files that you mention are part of the standard GAUSS library. So you should not have to #include them in your file. Try commenting out those statements and see if your code still runs.
In the case where you do want to execute the equivalent of an #include from the GAUSS command window, you can use the 'run' command instead:
run myfile.ext
instead of
#include myfile.ext