The current custom build linked from the Getting Started post won't launch on Yosemite. Immediately upon double-clicking, an error window pops up with...
“Arduino” is damaged and can’t be opened. You should move it to the Trash.
Initially I was thinking it was because this custom build wasn't signed, but that error is different, and can be worked around by simply right-clicking and choosing "Open" from the context menu.
So, any thoughts? And yes, I've redownloaded the zip file a couple times to make sure it wasn't a legitimately corrupted download (which I've never actually experienced, but worth a few seconds to confirm).
[EDIT] Console shows the following every time I try to launch "Arduino"
6/3/15 12:47:58.399 PM CoreServicesUIAgent[7047]: Error -60005 creating authorization
6/3/15 12:47:58.452 PM CoreServicesUIAgent[7047]: Error SecAssessmentCreate: The operation couldn’t be completed. (OSStatus error -67030.)
[EDIT 2] It looks like this may be a bad cert, as opposed to no cert. See here.
[EDIT 3] More info...trying to manually allow it through gatekeeper didn't work, but it will confirm the problem...
> spctl -a -v Downloads/Arduino.app
Downloads/Arduino.app: invalid Info.plist (plist or signature have been modified)