For just your own skin, you need to tell which car it is so we can tell the name of the file. Place it in the vehicle folder of the installed folder from your data section. For me for Megane as example: e:\games\rFactor2\Data\Installed\Meganes\1.0\M2009_02ALT.dds Save it in DXT5 with minimaps.
That´s a good question! How about the Formula Renault 3.5? I´ve downloaded the Template files, and the plugins for DXT files for photoshop, but i can´t get it to install... =/
This is indicated in this thread/post: http://isiforums.net/f/showthread.p...racks-Templates)?p=20193&viewfull=1#post20193
Unfortunately, there is a bug putting them in the userdata folder as instructed in that thread, you get the whole skin reflected in the windshield (as well as on the car where it should be)... putting them in the destination that Marco mentioned (for the Megane) alleviates this bug/feature.
I haven't tried it yet, but would it help to flatten the image before exporting to DDS? Update: It didn't