I'm trying to get the following addons on to some models
a Darth Vader cape on an ARC trooper
a backpack on a Scout Trooper
get rid of the cape on a magnaguard model.

How do you get capes and backpacks on models so they work in SWBF 1

as far as i know "cloth" as it is in bf2 does not work in bf1, only the speciall addon capes that vader and dooku have, which i think are animated meshes, so no cloth, addon meshes however should work here is the tutorial for adding addons to models.
How to hex edit addons onto another model tutorial by Deviss