Create your main working folder of your addon (you can name it as you like).
Into this main working folder, create another one named for this example “HMMWV” (inside this folder you will have your addon main 3D file so you can name it according its name).
Into “HMMWV” folder, create these three folders … “data” - “penetration” and “weapons”.
From ArmA 2 samples folder go to … A2SM_Data_APL/Wheeled/CA/Wheeled/ … find the “HMMWV50.p3d” and copy paste it into your “HMMWV” folder (root - not inside any other folder).
Now open the copied “HMMWV50.p3d” into Oxygen2.
From Oxygen2 top menu go to … Tools –> Mass Texture & Material Renaming (you will see a full list of files and their original location - path - needed for your addon)
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Now you must extract (unpbo) every original ArmA 2 pbo containing these files listed into “Mass Texture & Material Renaming” editor (we need that as the ArmA 2 samples does not contain the texture files).
Assuming that you have all needed original pbos extracted, you must now copy - paste what is listed into “Mass Texture & Material Renaming” to the appropriate folders of your addon (note : data to data, penetration to penetration and weapons to weapons folder - look at the path of each file. Also in place of any file with “TGA” extension you will find and copy - paste the “PAA” ones).
When you'll be ready, you have to replace the paths (one by one) using “Mass Texture & Material Renaming” editor … to do that … click (for example) on the first in list ca\data\data\default_flash_2pass.rvmat … now right below we must put our path which must be YourMainAddonFolderName\HWMMV\data\default_flash_2 pass.rvmat … then hit “Rename” button and proceed to the next file (you will notice that each new path is now coloured in “black” into your list … in case it is still coloured in “red” it means that either the path you are stating is wrong or you haven't pasted this file into your folder as described above).
When you'll finished with all paths your list must contains only black lines and you can close the “Mass Texture & Material Renaming” editor. Save your p3d file now.