Include and add to project file paths also limited

$I

and

  UFRMAbout in 'UFRMAbout.pas' {FRMAbout},

and such cannot be used with $(Config) or $(Platform) or

the must desired $(CompilerVersion)

or anything for that matter:

{$I $(ProjectSource)\config.inc}

^ Example of which would be nice.

Or instead of

..\..\..\libraries\etc in blabla.pas

$(ProjectSource)\libraries\etc

Bye for now,
  Skybuck.