Thanks for the clarification again, DHalens !
Spritz is a curious program and I've found very little info about all its details in the forums (the few that are there are too short and, it seems, related to a previous version). With Synaptic, the routine was "reload" to refresh the repo, and then "Mark" to allow all updates, and that was it.
I'm not quite sure how the routine with Spritz should be:
1. The one default repository is enough?
2. Should I "Update Repositories" often?
3. What is "Regenerate Cache" and what does it do?
4. I have 3 "Security Advisories" which refuse to install ("Packages not found in repositories, try again later") although my packages are Sabayon 4.0 default ones with no external programs
5. Is Spritz, anyway, the quicker, safer, way to update my system or am I missing on something else?
Thanks for your time!