TIE Fighter Workshop
From Emperor's Hammer Encyclopaedia Imperia
TIE Fighter Workshop (TFW) is a program used to develop custom TIE Fighter battles and missions. There is an Imperial University course which teaches the basics of using TIE Fighter Workshop here and is highly recommended.
The help functionality in the TFW application no longer functions with modern versions of Windows. Documentation can now be found on the wiki page TIE Fighter Workshop Help Manual.
Detailed information on creating a custom Battle Bitmap can be found here.