Instructions
Click "Start" and "Computer" and navigate to the XML folder in the Star Wars: Empire at War game. It most likely looks something like this: C:\Program Files\Lucasarts\Star Wars Empire at War\GameData\Data\XML
Open the "Squadrons.xml" folder. Locate the line that begins with "<Required_Star_Base_Level>." Highlight the entire line and press "Ctrl" and "C" on your keyboard to copy it to your clipboard.
Click "Start," "All Programs," "Accessories" and "NotePad" to open the text editor.
Press "Ctrl" and "V" on your keyboard to place the line of XML code into NotePad so you can edit it.
Change the number after "<Required_Star_Base_Level>" to "0." This makes it so you can build units regardless of your star base level.
Copy the edited line of code and go back into the XML folder. Replace the original line of code with the edited line of code.
Open the "SpaceUnitsFighters.xml" folder and locate the "<Required_Ground_Base_Level>" line. Highlight and copy that entire line.
Go back into WordPad and paste the line of code you just copied. Change the number after the first ">" to "0" so you can build units regardless of your ground base level. Copy and paste the edited line of code over the original in the XML folder.