I just cut a quick new beta build of X-Plane 10.11 - Jörg fixed the Linux crash. The crash was a problem with the plugin .so's and we don't even know how the bug happened, but it's fixed now.
Linux users: since the crash is at startup, you won't be prompted to auto update (because X-Plane crashes before the auto-update check can run). So to fix your beta installation, re-run our installer and pick "update x-plane" with the beta box checked. You'll get beta 3 and be back in business.
We'll fix more bugs next week, and the rate of betas may slow down, but we'll try to patch crashes as quick as we can.