Once you have your file ready to export, you should find a similar functioning weapon in Game Guru\Files\gamecore\guns and duplicate the directory for it along with all of the files inside.
Then, export your scene and overwrite the hud.x file. This is the file that contains the FPS weapon.
Next, you will need to overwrite the gun_D/N/S.dds texture files with your own textures for your weapon. You need to have the hand and weapon textures all on the same sheet in order for it to work correctly and this is hardcoded to look for that texture set.
Then, open the gunspec.txt in a text editing program and change the animation values and other settings to work with your new weapon.
At this point, it's best to test in-game by directly assigning to the player marker and then fine tune from there.
Eventually, you will need the lowpoly world model and pickup item version in Files\entitybank as well as the 3rd person weapon model which is the VWEAP.x in the gamecore folder.
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