Final Cut Pro X keeps crashing even after re-installing...

Hi all,
Nice to meet you guys!

Here's what happened..yesterday when I edited a video, it keeps saying that the startup disk is full.
So then I let it 100% saved, then quit the app.
However, this morning when I tried to open it start to keep crashing - I've done a lot of clean-ups for the space, back-ups, cleaned reference, even re-install still doesn't work.
(**ps: My FCPx version is 10.1.3 / System is OX S Yosemite, Version 10.10.5 )

Here's the brief info from the crash report:

Process: Final Cut Pro [1350]
Path: /Applications/Final Cut Pro.app/Contents/MacOS/Final Cut Pro
Identifier: com.apple.FinalCut
Version: 10.1.3 (251130)
Build Info: ProEditor-25113000038000000~1
Code Type: X86-64 (Native)
Parent Process: ??? [1]
Responsible: Final Cut Pro [1350]
User ID: 501


Date/Time: 2017-04-14 20:20:30.952 -0400
OS Version: Mac OS X 10.10.5 (14F1909)
Report Version: 11
Anonymous UUID: FD25D6E8-EF75-1AF3-6C41-D9E3BE292FA2




Time Awake Since Boot: 1600 seconds


Crashed Thread: 0 Dispatch queue: com.apple.main-thread


Exception Type: EXC_CRASH (SIGABRT)
Exception Codes: 0x0000000000000000, 0x0000000000000000


Application Specific Information:
*** -[__NSPlaceholderArray initWithObjects:count:]: attempt to insert nil object from objects[0]
abort() called



Thanks for reading all these..Hope there's any suggestion for help, thanks again!

Before doing anything else, be sure to leave at least 15% to 20% of free space on your system drive. Once that's done, you should have your media and library on another external drive for editing (with ample free space as per above). I'm guessing that is the main cause of your problem to start. There may be other issues, but that's the first thing I would correct.