1) Locate the Bitmaps folder inside the Tassman folder. On PC this folder is called Bitmap.
On Mac: HD/Library/Application Support/Applied Acoustics Systems/Tassman 4/Bitmaps
2) Make a backup of the Bitmaps folder.
3) Drag the new files (controls, backgrounds, frames, words) into the Bitmaps folder to replace the originals.
4) Start Tassman.
HOW TO DE-INSTALL
You can restore the original user interface by replacing the Bitmaps folder with the backup you made in step 2.