> Has SciTE been updated to handle the QT libraries, for I only see a "gtk" make folder.
The standard distribution of SciTE only supports Win32 and GTK+ on Linux.
> I'm guessing that the "outer layer" of SciTE would have to be re-written for QT, and I have a feeling that the commercial version of SciTE in the Mac App store may be that QT port.
The Mac version of SciTE calls Cocoa directly. It does not use Qt.
> If so, I'm guessing source will not be available.
I have no current plans to publish the source code for OS X SciTE.