Cubase pro 8.5.20 won't load in El Capitan

I’m running Cubase Pro 8.5.20 on my early 2008 Mac Pro 2x2.8 quad core xeon with 32 Gb of ram.
It ran great under Yosemite but now, after upgrading to El Capitan, when I try to boot , it says: Application’’ could not be started and probably the file is corrupted or incompatible, or file access permissions are set incorrectly. Download latest version of Licenser.

When I try to boot that it says there’s a communication issue.

So, I’m out of business.

Any suggestions wold be greatly appreciated!

John Paris