If you dont make it crossplatform, I (and possibly Sol) will hunt you down! (He knows where you live, see).

Introduce a command set for each platform, specific to that platform.
Allow both project settings and pragmas (in the code) that can be used to enable the use of these platform specific libraries and commands into rgd.
eg: msw_LoadDLL, lnx_ToggleWorkspace, would only be available when one of two things have been done:
change project settings to allow using commands specific to that OS (obviously forces compiling to that OS only), OR
pragma use mswindows;
If someone goes pragma use mswindows and someone else includes their code in their program, with pragma use linux, error: cant compile these into the same program (even if their two seperate compilation units, of course; So its not a pragma in the sense of file scope, rather it determines entire project settings ... You dont exactly want to go into RGD having makefiles afterall

).
I assume you have a context sensitive inclusion system, eg: if someone uses a CreateWindow command, it issues to use that library?
You could always try and do the same with platform specific features, then issue a warning that its more sensible to explicitly mention that by going 'pragma use mswindows' somewhere in one of your scripts (though ideally at the top of every modular section).
You can always mess up your ide with preprocessors if its windows gui functionality thats in the way.
And you can always have the platform specific libraries communicating or even extending the ones built in.
And an RGDDX9 extension etc.
If not for the children, ... Do it for your own sense of self satisfaction.
