Hello, to set the engine to show normal and specular maps, you need to go into the matrics panel during test game (Tab Tab) and set the entity shader to highest.
F1 - F4 are for light mapping.
Naming format of your texture files should be like this.
somefile_d.dds for diffuse
somefile_n.dds for normal
somefile_s.dds for specular
Intel(R) Core(TM)2 Quad CPU Q6600 @ 2.40GHz, 2400 Mhz, 4 Core(s), 4 Logical Processor(s), 8gb RAM, Nvidia gtx660, Windows 7 Pro 64bit, Screen resolution 1680 x 1050.