I don't think its an issue with the i model but is with the the textures,
It seems like the speculer texture is coming through the defuse map causing a bleed through so you may have to lower the brightness /saturation of those textures.
Also check to see if textures are exact duplicates. And not over compressed
So I would start from the beginning
1# texture save as .dds and then make your other textures from 1# and save each one as .dds
Make sure you select the .dds option and not type it in after the file name during save as I have had simular
Problem due to typing in the file extension upon saving, don't know why but just cause's an issue.
Also have a go at using a GG stock texture with its D/N/S
And see what result you get
Hope there is some helpful info here.
Keep us updated )²