Apple have released the latest update for OS X which is version 10.9.5.
In our testing we found that it breaks the code signing "signature" which we added to Hauptwerk 4.1 (this informs you that we are registered with Apple as a software developer and that our software is safe to install). Now if you attempt to install Hauptwerk 4.1 on OS X 10.9.5 the OS X Gatekeeper software will attempt to prevent Hauptwerk from installing.
We're updating our code signing to be compatible with this new version of OS X for Hauptwerk 4.1.1 which will be due out shortly (along with other bug fixes and some other updates since the release of version 4.1.0).
In the mean time if you need to you can still install Hauptwerk without issue on OS X 10.9.5 by bypassing Gatekeeper. For detailed steps please visit
here.