Hi. I'm trying to open DCP-o-matic on a MacBook Air running 10.13.3 Beta (17D39a) and am experiencing a long hang whilst it tries to verify DCP-o-matic 2 followed by the legend...
“DCP-o-matic 2” can’t be opened because the identity of the developer cannot be confirmed."
This problem is usually solved by going into System Preferences > Security & Privacy > General > Enable 'Allow Apps To Be Downloaded From Anywhere' but in this instance that doesn't help.
I've tried both the latest test build as well as the standard download, both with the same result, and this issue has been present for 12 hours now.
I had this issue a couple of times as well somewhere between 2.11.20 and 2.11.30. Another thing that seemed to be linked to it was very slow downloads, or interrupted downloads. Must have been a problem with the server or the internet connection. Anyway, I tried the usual suspects, but in the end, I only got rid of that issue by downloading again. I had it in Sierra. First time that was, and believe me, I download new versions often.