Hi Greg,
the exact text of the error would be useful, because the text says exactly what is wrong, and hence exactly what must be done to fix it. Post the exact text, and I can give you the straight answer.
>> What do I do about a certificate that needs to be installed on lots of machines?
that's not likely to be the problem.
I'm guessing it's complaining about ca_root.pem - which you can copy from the netdemo app and just include in the application folder as part of your install.
cheers
Bruce