Most of the information can be found in the sourceforge page
Run this in a terminal
curl https://sourceforge.net/p/continentalsupplieshedgewars/code/ci/master/tree/release/Continental_supplies_1.6a.zip?format=raw > /tmp/t.zip && mkdir -p ~/.hedgewars/Data/Scripts/Multiplayer && unzip /tmp/t.zip -d ~/.hedgewars/Data/Scripts/Multiplayer
Restart hedgewars
curl https://sourceforge.net/p/continentalsupplieshedgewars/code/ci/master/tree/release/Continental_supplies_1.6a.hwp?format=raw > ~/.hedgewars/Data/Continental_supplies_1.5e.hwp
Download the latest zip version from Link and extract it to My Documents/hedgewars/Data/Scripts/Multiplayer, if the folders does not exist then create them.
*Note that C:\Program files\hedgewars\... is the wrong directory!
Restart hedgewars
If you also want to try the own weapons mod head to the store (Link) and add something like this to the script parameters: