The Alsa documentation states very clearly that you must have a complete copy of the kernel source for it to build. So, I don't think the kernel headers are enough. By the way, looking over the ChangeLog for Slackware current, they've added Gnopernicus and Gnome-speech. They are calling it beta 2, so I expect a release fairly soon. It also mentions briefly that a menu has been added to control what gets started at boot time.
