This post has been marked by the post author as the answer.
Just name them the same as the _D texture but with _N _S etc. instead, make sure the _D texture is listed in the textured = line in the .FPE and Gameguru will do the rest.
Unfamilia did a good series of videos on how to get models into GameGuru, check them out:
[img]belidos3d.swgrp.co.uk/wp-content/uploads/2016/03/blogo.png[/img]
Primary Desktop:
i7 7700,k NV1070 8GB, 16GB 3200mhz memory, 1x 2TB Hybrid, Win10.
Secondary Desktop:
i5 4760k, NV960 2GB, 16GB 2333mhz memory, 1x 2TB Hybrid, Win10.
Laptop:
i3, Intel 4000 series graphics, 6GB memory, 1x 500gb HDD, Win8.1.
