Same problem here with [El Capitan 10.11.6] from last night.
things I’ve tried like:
exactly same problem this afternoon after the upgradding the latest version !!! ,
I’m having the same issue as I had at the last update. I can’t get past “let’s go” it just crashes. Using El Capitan. Can’t Zwift on my MacBook Pro . Please advise as I couldn’t Zwift for at least three days last time this happened 
Hi I’m having the same issue on El Captain Mac book pro (model identifier MacBookPro3,1).
Do we need to be beta testers for this not to happen as its so frustrating and inconvenient.
Any update on y’all fixing this issue
Hi @shooj Just wondering if there are any updates? 
Any update on this issue?? Very frustrating. I’ve uninstalled, reinstalled, rebooted, double checked, triple checked, said a “Hail Mary” and “our Father”, tried a different bike on the trainer, changed back to my road tire in place of my trainer tire, mowed the lawn and tried again, ate dinner and tried again, used my old Sidi road shoes instead of my S-Works, put on my Hincapi kit as I wore that kit last time it worked, and on the then last attempt to launch, I wore my helmet. No dice. 
UPDATE: We’ve identified a fix and will roll it out in the next patch. Estimated date is mid-next week. Thank you for your patience.
I’m sorry but your post made me laugh out loud. Thank you 
Totally feel your pain though. Very frustrating
Follow up: after installing easy to obtain free download of Sierra (10.12), which takes about an hour… zwift is still running perfectly over several days…
Recommend this if you don’t want to wait for the patch
Plus might still run when the new update comes out next time…
That was the intention lol
Im happy to see we’ll be back on line and running Zwift soon.
Thanks so much for your efforts!!
Unfortunately my Mac is too old to update 
So, given your update, if we’re having an issue you won’t fix it until next week? I’m not going to be able to use Zwift until next week? That seems a bit ridiculous. Why can’t the patch be put out immediately?
Wow! Next week is a lot of down time 
Any chance the developers could let us use the previous build/version? That was working fine for me.
There are a lot of new issues this time, presumably they’re working on a number of fixes to be rolled out together.
Totally understand but it’s killing me! I have a two hour race tonight and then I won’t be able to access my modified training plan workout for the weekend 
Same here only use my old iMac 
for Zwift.
I’ve been using my iPhone until they fix the problem.
I have the same issue. I posted further down - 73. My issue may be the no vercur override found. I have OS X 10.10.5
With this release, we have ended support for OSX 10.10. Please see this other thread