uck-remaster-pack-rootfs will fail under certain conditions

when using uck-gui for a customization project I select the needed languages then specify that I want to perform additional operations. When given the option I use the shell to enable the universe repositories, go back to the package manager and install asterisk. As part of this operation asterisk is started. When the option to continue is selected the unmounting of certain directories fails because they are still in use (by asterisk) and the whole process fails.

I suppose that it is my responsibility to manually stop asterisk before the continuing, but I wonder if the installation of other services would cause similar issues for folk and if this could be handled by uck.