I thought I'd provide a quick guide of the file structure in Sol Unleashed for the benefit of those who want to take the mod and change it to suit their own playstyle better.

The main change is the addition of a new system initializer file, called "sol_unleashed.txt", which has the following structure:

(1) A Sol initialiser, which is similar to the vanilla Sol initialiser, except that:
(a) the solar system is more refined than that provided in vanilla (in my opinion!)
(b) the initialiser calls, in sequence, the 600 specific initializers for the stars around Sol.

(2) A Milky Way initializer, which generates a random system, then calls a Sol initialiser at a range of 100 to 300 (similar to the first one but different, because the empire tiles are not present on Earth), then calls the 600 individual star initializers.

(3) A Deneb initializer, which generates the Deneb system (much like in vanilla), then calls another Sol initializer (one which does not call the Deneb system), but at a range of 200 to 300, then calls the 600 individual star initializers.

(4) A Trek initializer, which generates a Sol system similar to that generated in (1) above, then calls most of the 600 individual star initializers, but blends them with 13 individual initializers for Trek Systems.

(5) A series of 22 initializers for the nearest star systems to Sol, each of which was individually designed, with some randomness.

(6) A series of 578 initializers for the remaining star systems, the design of which was partly automated, based on star size, with randomness included.

(7) The 13 Trek Initializers for the individual Trek systems.

The special_system_initializers file was amended to prevent a second Sol system spawning. The three Sol system possibilities in this file were amended to change the system from 'Sol' to 'Helios', and to change 'Earth' to 'Terra Nova'. Incidentally, with the Trek Systems option it is possible to see two planets called Terra Nova, one in the Helios system and one in the Eta Casseopiae system, but I don't consider this a big deal.

The 00_random_names file was amended to remove all the real star names (to avoid conflict with my mod), to add extra systems so the game can generate 2000 unique star names, and to add nebula names.

The sol_unleashed_l_english files simply ensures that the Milky Way System and Trek Systems option appear correctly in the start up menu.

The se_defines file places spaceports a little closer to the planet. I felt this was necessary because of the smaller scale used for the first three planets of the Sol system.

And that's all there is to it!