This is fixed upstream. I believe the attached patch should apply to both 0.4.0 and 0.4.1 if you're interested.
** Attachment added: "patch to manually close the About dialog with gtk 2.10.x" http://librarian.launchpad.net/5424742/agave-aboutdialog-close.patch -- About dialog "Close" does not work https://launchpad.net/bugs/75628 -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
