The Mac binary installer you are distributing (mandelbulber-mac-1.09.zip) includes a handful of pre-compiled binaries, and your install script copies these into /opt/local without regard for any files that may already be there. The /opt/local prefix is used by the MacPorts package management system; by installing files into that location, you are interfering with MacPorts, causing problems for our users, and increasing our support burden. Here is an example:
https://trac.macports.org/ticket/32709
We would ask you to distribute binary installers that install files into any other prefix, preferably one unique to your software. Good choices might be /usr/local/mandelbulber or /opt/mandelbulber.
Thank you for your assistance.
Sincerely,
Ryan Schmidt, for the MacPorts project