Stefan Blumentrath :
To underpin Jürgens point:
In my company we used "creatensis.pl" to create custom OSGeo4W installations with modified startup scripts (so users get prepared configurations.That worked quite well. Doing so for a "GRASS GIS standalone" installer might reduce maintenance, risk of bugs and confusion among users. So, I would definitely recommend to follow Jürgens suggestion.
winGRASS standalone is based upon OSGeo4W and the (dependency) packages there. just a simple re-packaging and adapting paths.
what do you mean by "Doing so for a "GRASS GIS standalone" installer might reduce maintenance, risk of bugs and confusion among users."?
kind regards
Helmut