but HOW can i create a new race?
This is very simple actually, although there are some issues:
As an example, let's create a new race with a different light frigate compared to the stock one.
First you go into your GameInfo folder. There you make a copy of the
PlayerTech.entity file. Rename it to
PlayerShadows.entity (this is not really necessary, but helps a bit in remembering which file does what. Quite important imho

).
Open it with notepad. Change the
raceNameStringID "IDS_PLAYERRACENAME_TECH" to
raceNameStringID "IDS_PLAYERRACENAME_SHA".
Strings are how you give descriptions and names to things. Basically they're just there for fluff. The corresponding lines can be found in the
English.str file in the String folder.
So we now open the above mentioned
English.str file with notepad (everything opens with notepad, btw.) and search for
IDS_PLAYERRACENAME_TECH. Duplicate the
StringInfo
ID "IDS_PLAYERRACENAME_TECH"
Value "TEC"lines and change the duplicate to:
StringInfo
ID "IDS_PLAYERRACENAME_SHA"
Value "SHA"No we need to change the second line of the file
NumStrings 3499 which is the number of strings in the file. Because of our duplication we have one new string, so add one to the number displayed there. (The number may vary from mine, since I already did some modifications there.)
Now we come to the most important file, the
GalaxyScenerioDef.galaxyScenerioDef file in the GameInfo file. Every important thing in the game needs a definition in this file to be placed.
At the end of the file, there is the following:
playerTypeCount 1
playerType
designName "Tech"
entityDefName "PlayerTech"change it to the following:
playerTypeCount 2
playerType
designName "Tech"
entityDefName "PlayerTech"
playerType
designName "SHA"
entityDefName "PlayerShadows"playerTypeCount needs an increase of one because we've got one more player. The entityDefName shows Sins the name of the new player file:
PlayerShadows.entity.
Now, if I didn't forgot something, you should have a new selectable race.

Now let us add a new light frigate for your race. First, make a copy of
FrigateTechLight.entity and rename it to
FrigateShadowsLight.entity. Open it and change
NameStringID "IDS_FRIGATE_TECHLIGHT_NAME"
DescriptionStringID "IDS_FRIGATE_TECHLIGHT_DESCRIPTION"to
NameStringID "IDS_FRIGATE_SHALIGHT_NAME"
DescriptionStringID "IDS_FRIGATE_SHALIGHT_DESCRIPTION"go into the
English.str file, search for
IDS_FRIGATE_TECHLIGHT_NAME and duplicate the following lines:
StringInfo
ID "IDS_FRIGATE_TECHLIGHT_NAME"
Value "Cobalt Light Frigate"
StringInfo
ID "IDS_FRIGATE_TECHLIGHT_DESCRIPTION"
Value "A workhorse combat frigate that can be upgraded to efficiently defeat other ships with abilities."Change your duplicate to the following:
StringInfo
ID "IDS_FRIGATE_SHALIGHT_NAME"
Value "Shadows Light Frigate"
StringInfo
ID "IDS_FRIGATE_SHALIGHT_DESCRIPTION"
Value "A pwning frigate of doom. Defeats entire AI fleets alone."As above, add two points on the second line to NumStrings. (If you ever forget to change the counts (and almost everything is counted in Sins files, your game will crash. Thankfully the crash will tell you what is missing, so its easily fixed. Usually.)
Now we go in the important
GalaxyScenerioDef.galaxyScenerioDef file again and duplicate
planetItemType
designName "Tech:Frigate:Light"
entityDefName "FrigateTechLight"and change it to
planetItemType
designName "Shadows:Frigate:Light"
entityDefName "FrigateShadowsLight"A bit up is another count called
planetItemTypeCount. Add one to it.
Now last but not least, open your
PlayerShadows.entity file and change the line reading
entityDefName "FrigateTechLight"to
entityDefName "FrigateShadowsLight".
You now have your own light frigate, congratulation. Just for fun, go in to the
FrigateShadowsLight.entity file and change
PreBuffCooldownTime 8.000000 to
PreBuffCooldownTime 4.000000. Your frigate now shoots twice as fast. Pwning time.

------------------
Issues:
If you got a crash, it's mostly because of some misspelling or because you've forgot to change a counter. Also there has to be an empty line at
every file, or the game will crash.
If you're unable to play as your race, try changing
selectablePriorty 2 in the
PlayerShadows.entity file to 1. Although this may make the game to chose this race for the AI as well. :/
To add new models, you'll probably need 3d studio max, which I haven't atm. So I can't help you with that.