This has been driving me nuts since I got the first OS X 10.11 beta.
Every time I launch, I get this error

And I'm getting the same whether I run in Windows / Virtual Box or OS X.
What's particularly vexing is that it doesn't matter if I sync my system to time.apple.com, any of the other Apple time servers, time.nist.gov, etc. It just never works.
If I disable network connectivity at startup, then I can get into the app, but it is almost completely unusable. I can't save and it crashes almost immediately whenever I do anything.
I get that OS X betas are unsupported, but this seems like something that shouldn't ever matter - much less when the time settings are actually fine. It doesn't help if I set my time zone to GMT or Portland time.