Slyforion

I have downloaded some custom maps for Yuris Revenge. I have placed the downloaded maps in my Maps/Custom folder under root. I have various maps with .map and .yrm extensions. Some maps have both a .yrm and a .map version. Most of my maps are not showing up the preview picture in cncnet. I can play the maps, its just that I cannot view the preview in the shell before the game starts. Are there any standard protocols for how I should go about downloading custom maps? I don't really know the difference between .yrm or .map. If anyone could answer or point me to a thread that contains the answer, I would appreciate it. Thank you!

I don't know if anyone can help me with this. I have both ra2 and yuris revenge installed on my machine. RA2's executable can take a switch of -CD which allows for the game to run without a CD. However, the same switch does not work for YR. Does anyone have any ideas? Thanks.