First thing is that you need to make sure that you are rooted and you have fully installed CWM-based clockwork recovery. Know how to reboot into and navigate in clockwork recovery. Using your capacitive buttons. Menu=down, Home=up, Back=back, Search=select. If you haven't done all this yet then research this stuff first.
1. Download the rom from the site linked in the original post. The lastest at the moment is UNL3ASH3D_V1.1_UPDATE_FINAL_SIGNED.zip
2. Do not unzip the file. Leave it as it is.
3. copy this file to your external SD Card. Not the internel memory. Put it in the root directory of your sd card which means do not put it in any folder.
4. Not required but I would suggest checking the MD5 hash to verify the file is good. The MD5 hash is shown under the link to download. You can download a free tool for windows that will verify the MD5 hash for you.
5. Reboot into Clockwork recovery CWM-Based Recovery v4.0.1.5.
6. Select "wipe cache partition" scroll down and select "yes" to accept.
7. select "advanced". then select "wipe dalvik cache" scroll down and select "yes" to accept.
8. may have to use back key to navigate to first tier of menus. select "mounts and storage" then select "format /system" then scroll down and select "yes" to accept.
9. may have to use back key to navigate back to first tier of menus. select "install zip from sdcard"
10. select "choose zip from sdcard" select the file you downloaded. agree or select yes for any prompt to proceed.
11. Once the installation is done then select" reboot the system now"
12. The first boot will take a while so don't worry unless you used a corrupted file or something.