If you read the first post, it explicity says "cwm only". It is not a safestrap rom. Also, liberty is based on the Droid 3 stock rom. If you want to port it, here are the first steps:
1. Get an updated Safestrap rom that incorporates the lates Motorola patch. (We will want the performance and battery boost it gives the d4)
2. DeOdex the ROM from step 1.
3. Prepare a sort of blank slate to start with, by ripping out everything not necessary.
At this point, we can start adding the Liberty customizations.
Sent from my DROID4 using XDA