Here are the steps for installing the true sidereal settings into Prometheus:
Step 1: If you are using Prometheus for the first time, or if you don't have any of your own files or settings saved download the whole folder and replace the existing folder found under "My Documents" with this updated folder. (Be advised that this option will permanently remove any saved files and settings you have created up to this point in Prometheus.) If you choose this option simply proceed to Step 2 below.
If you have files already saved in Prometheus then you can download the individual files. Place the files in their appropriate CapricornPROMETHEUS folders (found under "My Documents"):
Astrology Systems > Zodiac13 Configurations
Zodiac 13 Basic Wheel
BiWheel Zodiac 13 Basic Wheel
TriWheel Zodiac 13 Basic Wheel
Synastry Aspectarian & Wheel
10 Planets + ASC + MC + NN + SN + Chiron
7 Planets + ASC + MC + NN
5 Planets + ASC + MC
Outer Planets + NN + SN + Chiron
Step 2: Open Prometheus and click "Astrology Settings" on the top-right of the screen.
Save your current settings by clicking "Save...".
To load the new settings click "Load..." and select "MTZ Settings".
Click "OK and Save" on the main Astrology Settings window.
Then restart Prometheus.
You now have the new settings loaded into the system and can revert back to your previous settings at any time by loading them the same way.