Use the editor. It can be found on the quickstart menu. Go to each tech, and increase the cost value by however much you want.

 Or you can do this (pasted from post by braddock8)

Increasing research costs the easy way

By Braddock8 Posted June 24, 2008 01:02:26

For some people, myself included, "Very Slow" research times just aren't quite slow enough. Particularly if you like long, drawn-out games on Gigantic and Immense galaxies.

The solution is simple, but tedious. Go through all the tech trees and manually increase the cost of each and every tech in the game. Well, I really don't have the patience to do that, so I came up with an easier way.

Open up TechTree.xml with a text editor (i.e. Notepad). You'll find it in the GalCiv2\Twilight\Data\English directory for Twilight, GalCiv2\DarkAvatar\Data\English for Dark Avatar, or GalCiv2\Data\English for Dread Lords.

First thing you need to do is save a backup copy, for when you want to go back to normal research speeds.

Now, open up the editor's Replace tool, and replace every instance of "</Cost" with "0</Cost" And that's it. With a single mouse click, you've increased all the research costs tenfold. For Twilight of the Arnor, you'll also need to do this in each race's individual tech tree file. Again, remember to save backups.

For comparison's sake, I recorded the different research times for Terrans' Artificial Gravity at the very beginning. I used a Large map with common everything.

Original speeds:
Very Fast: 5
Fast: 6
Normal: 8
Slow: 11
Very Slow: 22
Increased Speeds:
Very Fast: 52
Fast: 62
Normal: 78
Slow: 111
Very Slow: 225

Ok, i did this. But now i'am struggling with the Start "Tech Points" 8custom race) - those 200 defaul aren't enought anymore. So, how do i Increase these points?

Since you don't care about MV, you can edit the raceconfigxml file and add in new techs that your race can start with, like so:

<Tech>NewPropulsion</Tech>

You can either edit the raceconfigxmls saved in \My Documents\My Games\<appropriate GC2 folder here> or if you'd like you can just edit the base game files in \Stardock\TotalGaming\GalCiv2\Twilight\Data\English\RaceConfig.xml or equivalent (replace \Twilight with \DarkAvatar or look in the root directory of \GalCiv2\).

But Scout is correct, to my knowledge, that you can't arbitrarily increase the points available to spend.