23.8.5.8707 does not work anymore on Macosx 10.9.x

After downloading the support-client a mesage is thrown the file is corrupt.

If I download the permanent client, it will install but then wont launch.

In general, the software should be able to work on any verion, or at least most versions of an OS. Like for example Teamviewer. You can AFAIK still download a TV version for W2000, or MacOSX 10.4. It just works.

Is this a bug?