Thread moved to the distro category.
For #1, I reviewed the settings for the TangoPBX Distro category, and there’s nothing there that should prevent you from posting. To make absolutely sure, I impersonated you briefly and confirmed that your user is not blocked from posting. Try again.
For #2, if you check the installing walkthru I posted, there’s a note about a delay after choosing the option to install from the grub menu, but it would be easy to miss.