It is currently not possible to change that. Please can you open a bug report (feature request) at https://bugzilla.proxmox.com/ - I guess this is easy/fast to implement.
Well, that username is a real mess Using 64 characters for the userid is nonsense...
I suggest that you set the "username_claim" property to use another claim as username (maybe email).
Our software is licensed as AGPLv3, so you need to tell your users what software it is, and provide a download option:
See: https://www.gnu.org/licenses/agpl-3.0.html
Da geht ganz sicher nicht (2 VM die gleichzeitig die gleiche Ressourcen verwenden). Außerdem ist der Zustand der kopierten VM anders als der der orginalen VM, d.h. du bist maximal inkonsistent!