Ardour was compiled with gcc4, your system uses a newer version of the standard c++ library. Plugins on your system may not load or plugin-UIs may cause crashes.
Mixbus has some “new” installers. Where can I get them for Ardour?
Really? I payed. But “only” one time. Maybe thats not enough…
We do releases, and nightlies. The current release is 4.4 (though 4.5 is imminent). Nightlies are not supported, but they make it possible for people to try out the very out latest code. This is a service we provide to ardour.org subscribers, not to all paying customers and not to everyone else (though we do make free/demo versions of the nightly builds available too, which allows anyone to test them).
Its your choice which users you’ll give a “latest code” support, I don’t like it.
No, the “latest code” is available to anyone and everyone, without charge. Fetch it from git and build the program yourself, any time you like. Nothing will stop you from doing this.
Built versions, which require continuously running, automated build systems, uploading and downloaing of significant amounts of data - yes, these are things that we limit access to, essentially to people who provide significant financial support to enable continuing development and bug fixing to continue.