:: How can I determine if texture/texture directory is standard resource for Nexuiz or not?
I should have maybe said it explicitly. Test your map with the plain nexuiz dir and you should see missing textures, etc. Basically this way you create a test environment where your map appears as it would to any other old user just downloading your map.. I should have been more clear about this. If a texture shows as missing via this method you know it's not included in nexuiz
