To install this ROM:

Make sure your device is rooted.
Download the ROM from the link given and copy it to the root of your SD card.
Power your phone off and reboot it in recovery.
To backup your existing ROM, apps and data, take a nandroid backup.
Use the main recovery menu to wipe all data and cache. Then go to the advanced menu and wipe dalvik cache.
Get back to the main recovery menu and select ‘install zip from sd card’. Select the ROM that you copied to your SD card in step 2, and wait patiently while it is flashed to your phone.
Once the flashing is done, reboot your phone


To Root you Desire HD

The first step is to launch Market on your HTC Desire HD.
Once you are in Market, search for VISIONary and install the app.
Once you are through installation, you will see a yellow VISIONary triangular app icon on home screen.
Now launch the VISIONary app, follow onscreen instructions and wait for a minute or two. You can also select “Run On Boot” option if you want your Desire HD to remain rooted every time you reboot your device.