This avatar works best in desktop mode (because of the custom pose) If you want to use this avatar in vr you need to remove the 'pose' in the custom override 2 which is set to the standing animation in the avatar descriptor script.
If you have any problems with uploading the model, you can find in the VRChatMods Discord server as 'Metal Nips' in greek letters and messege me.
We're now allowing modified SDKs to be linked in the description. Make sure you have the poly count in the name and stating above the link that its a modified SDK