If the Vector Linux people can make it work there must be a way to make it work with SalixOS. I may have to play with it and see what I can do. No promises, of course.
I have found some bug reports about it at the time, but they offered no solution. Anyway, it took me less time to write salix-update-notifier than I would have spent trying to figure out slapt-update-notifier instead.