First, we will modify an original texture from the game, this skin is used by elite tanks. We will change the german flag by a french flag on this Tiger tank
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This texture used is named elite_pack_german_COLOR.tga
So, let's use another original texture from the game fr_hanging flag_color.tga.
I won't explain here how to use an image editor like gimp, photoshop etc ... but don't change the name (elite_pack_german_COLOR.tga). Here's the result :
Now, it's time to replace the original skin by this one. Launch UABE and open unitmodels_WORK. Then click on "Info".
Now, sort by type (1) and find the texture (2) elite_pack_german_COLOR.tga. You'll find it in vehicules/elite_pack_german. And click on Plugins button (3)
From this Plugins window (1), select Edit then OK. A new window named Edit Texture 2D is opened (2). Click on Load button. From this window (3), select you're modified texture and click on open button.
Finish by clicking on OK button on Edit Texture 2D window. Now, back to the main window, click on OK button (1), UABE will ask if you want to save the change (2). Say Yes.
Now, you have to save in the archive which is used by the game named unitmodels
Find it on your subfolder "AssetBundles" and save.
You can now launch SS4 and test your work
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