GPL to NR2003 w/ Noonan Converter

I'm having a bit of a problem converting GPL tracks to NR2003. I
recently redid the whole GPL install and added the various updates
based on the directions that are found at Fred Faster's site. Each
update works and looks excellent in GPL.

However, when using the Dave Noonan converter, all APPEARS to go
smoothly, but when I load NR2003 and try a track (I have done Monza and
Monaco so far) I get a "Could Not Load Track" error. I have checked
"copy GPL patch files" box to allow the use of the updated track gfx.

Is there a known issue with some of the gfx updates? What could be
causing the problems?