Quick guide to converting icons:

-Put iconvert.mix in your Command & Conquer directory
-In XCC Mixer, go to [View] -> [Directories...] and make sure your C&C directory is set correctly.
-Restart XCC Mixer after setting the folder
-In XCC Mixer, enable the option [View] -> [Palet] -> [Use for Conversion]. This will make files yo convert to SHP adapt to the currently selected colour palette.
-Press [ctrl]+[p], and select icon_des.pal in iconvert.mix
-Navigate to the folder where your finished icons are
-Open the second file browser in XCC Mixer, and browse to the folder where you want your Desert icons to end up.
-Press [ctrl]+[p], and select icon_des.pal in iconvert.mix
-Select all your icon image files, right click on them, and select "Copy As SHP"
-Outside XCC, rename all the files from ".shp" to ".des" extension.
-Browse the second file browser to the folder where you want your Temperate icons to end up.
-Press [ctrl]+[p], and select icon_tem.pal in iconvert.mix
-Select all your icon image files, right click on them, and select "Copy As SHP"
-Outside XCC, rename all the files from ".shp" to ".tem" extension. Copy them all 2 more times for the winter and Snow theater, and rename those to .win and .sno respectively.