Any newbies around?

[narf poit chez BOOM]

Your homeplanet is automatically filled up; the only thing you can do is start with a smaller homeplanet. As for the other, go into data\TechArea.txt and mod all the start levels to 0.

[Ragnarok]

Low tech level is the most minimum tech you can get in the stock game. As Narf pointed out you can mod the files to change this but if you mod you should create a mod folder and copy the data folder from the stock game into that and mod those. It is never good to modify stock data files.