create a new .dds texture, and put it into the texture folder. give it a unique name. it doesn't matter what.
open up Commonres\textures.brf,
go to the Tex tab,
and click "add"
select the newly added texture, and in the "name" field, type the name of your new texture, then click Enter on the keyboard.
save the file (backup the old textures.brf first though)
open up Commonres\materials.brf
go to the Mat tab,
and click add.
in the Name field, type in the name of the material, then click Enter.
in the diffuse tab, type in the name of the texture without the .dds extension, and click enter.
in the Shader tab, select the shader that the previous material uses.
remember to press enter each time after changing the values, or they will reset.
to the left of where it says "Set" you'll see a number. this is a flag value, which sets various parameters. i find its better to type in this value as it is in the other material you're copying, and then pressing enter, rather than using the checkboxes.
after that, save the materials.brf(and backup)
now open up whatever it is the file the model you want to retexture is in,
and click "clone".
give it a new name, and in the Material textbox, type in the name of your new material, and then click Enter.
thats how far you'll get without the module system with this tutorial.
i'm not sure how to edit things with the text files,
but with the module system, you'd open up the module_items.py,
and search for the armour you want to copy. lets say you want to make a retextured Byrnie.
you'd find this:
["byrnie", "Byrnie", [("byrnie_a",0)], itp_merchandise| itp_type_body_armor |itp_covers_legs ,0,
1300 , weight(17)|abundance(100)|head_armor(0)|body_armor(39)|leg_armor(6)|difficulty(7) ,imodbits_armor ],
you copy and paste this text after any of the ], which basically means the end of an entry,
and where it says [("byrnie_a",0)] you swap that out with [("yourarmournamehere",0)]
the itp_merchandise property will ensure that your armour will eventually pop up in a shop, but if you want your player character to always start with this armour,
you'll need to modify module_troops.py
find the line where it says:
["player","Player","Player",tf_hero|tf_unmoveable_in_party_window,no_scene,reserved,fac_player_faction,[],
str_3|agi_3|int_3|cha_3,wp(150),0,0x000000018000000136db6db6db6db6db00000000001db6db0000000000000000],
this is the entry for the player. right after fac_player_faction, you have [] insert itm_yourarmournamehere or whatever your armour is called.
the itm_ prefix means that you're referencing something in module_items.
now open up module_info.py,
and change the export_dir to reference native, somewhat like this:
export_dir = "C:/games/mountandblade/Modules/native/"
change the slashes to /, since the windows standard \ causes errors when compiling.
now, run build_module.bat twice, as the first time around, everything hasn't been referenced properly yet, and you'll get loads of error messages.
you can get the module system here:
http://www.taleworlds.com/download/mb_module_system_1010_0.zip