Arma: Mod Folders
Custom modfolders are folders that can contain theme addons for easy selection, or Data files which change general parameters of the game. If you have OFP:Resistance, your \RES folder is an example of a modfolder.
Certain Flashpoint players prefer to put an "@" in front of each modfolder's name, so they get listed at the beginning of the Flashpoint folder, and can be easely separated from essential game folders.
To use Modfolders you have to create a shortcut to your OFP, and in the path add the folowing parameter: -Modname
"C:\Program Files\Codemasters\OperationFlashpoint\FLASHPOINTRESISTANCE.EXE" -nomap -nosplash -mod=@winter
Alternatively, you can use a tool listed on this page as "OFP Mod selector" , by Operator of Dissidence.
Mission modfolders
Within the Missions folder you can use subfolders, like in the example shown here. This cannot be done in the MPMissions folder.
Within the MissionModFolder, you can place an overview.html which, just like Single missions, can display an image and some lines of text.