Changes do not appear in saved games. The save files contain ALL of the information needed to make a game, INCLUDING all of the techs, races, and ship components. You will need to create a new game to make any mods show up.

I am wondering if I am changing the wrong file, cause I notice other folders that contain single player data items.

Im attempting to change the stuff in the Twilight expansion.  I figured it out.  In the ship editor, beside the size input box there is a box that says size mod.  What does that do?

You should not alter any file located in the TA install folder.

If you want to change something, aka mod s.th. , you should create a named modfolder within the Mods folder, if the mods folder does not exist create one with TA as parent folder.

If you want to dive more into modding, or want to study a quite complex race mod and how it is done,

you can download my custom race mod from the library ...

AsaRaceMod