Final Cut Pro Library Crash

I have a Library (Library A) which I have been working on for a long time. It was opening and being worked on fine up until about 10 days ago when I started work on another project (Library B). I then went back to open Library A and it has now started causing Final Cut Pro to crash. I have attempted loading all the Library Back-ups and they all cause the program to crash too. I can however, load Library B, along with other libraries, perfectly.

After a little bit of troubleshooting, I've found that I have another library that will not open. It was created on February 6th 2014. Library A was created on February 18th 2014. Library B, the Library that does open, was created on April 5th 2014.

In an attempt to resolve this problem I have (in no specific order):

1. Reinstalled Final Cut Pro X

2. Attempted to open Library A and it's backups on another machine

3. Created a new library in Final Cut Pro, then replaced it's package contents with those from Library A

4. Created a new library in Final Cut Pro, then replaced it's package contents with some of those from Library A (specifically the latest projects, in the hope of being able to save an XML)

5. Changed the timestamp on a copy of the old Library that wouldn't open using A Better Finder Attributes 5

6. Used SQLite on the Library file and all event files as per this tutorial https://discussions.apple.com/thread/5810717?answerId=25341423022#25341423022

7. Created a new library with the same library name, event name, and project name as the project I want to access, then copying the relevant 'current version.fcpevent' file into the package (which doesn't cause the program to crash, but means the project is just not read by FCPX)

none of these things have worked (though some, such as 4., bring me tantalisingly close, actually loading the Library, but then crashing as soon as I select a project). I am at a total loss, I anyone has any advice on how I can save this project I would be extremely grateful.