Agree with @jthi here - OnModuleLoad is basically a pseudo-function to receive arguments from another module at creation time - useful for creating things like launchers that instantiate other modules.
Below are the default arguments included in a Module script - anything that uses the symbols created by the Module has to be placed after the thisModuleInstance << Create Objects;
line:
// This special function will receive parameters passed to CreateInstance()
OnModuleLoad({},
);
thisModuleInstance << Create Objects;
// After this point your module instance objects have been created
// and can be referred to by name (for example, "Button1").