I think you might have to rename the race folder and files to Neutral### (with numbers instead of ###) to get them to be loaded by the game, but I am not sure on that part.
No...unless shomething has changed in 1.84 they can be named the same was as normal races. And yes...regular races will work that way...but I was hoping for some fresh meat. Hehe...
I will check the mods forum tho...didn't find at first...maybe get lucky this time.
If you're just looking for new race pics to use as neutrals and not entire shipsets then check out this... NewRaces(Redux).zip
It was slapped together a little while ago to replace the standard race (just to shake things up a bit) pics but it also includes many extras IIRC. Just name them as you want, throw in some history, and Bob's your uncle.
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I do not know with what weapons World War III will be fought, but I know that World War IV will be fought with sticks and stones.
-Albert Einstein