OK, I just checked it out. Are you sure you selected the right aircraft in FS9? I had to modify Aircraft.cfg for it to be listed on the selection menu & for the textures to display.
[fltsim.1]
<-- Change this to [fltsim.0]
title=Gulfstream 100
sim=G100
model=
panel=
sound=
texture=
custom
<-- Add the folder name extension in blue for the textures to display
kb_checklists=G100_check
kb_reference=G100_ref
atc_id=YV-669C
ui_manufacturer=Gulfstream
ui_type="G100"
ui_variation="LiderDesigns"
description= The former IAI Astra, now G100 is the smallest of the gulfstream bussiness jets. Designed FOR FS2004 by Peter Brun / LiderDesigns
Don't forget to install the Gauges from Gauges.zip to FS9\Gauges (or the Panel folder of the G100). It will be listed on the selection menu under Gulfstream as manufacturer. It has a 2D panel & VC. See below.