I used some Agfa stabilization materials around 1980 so will try to give you some answers.
1. they were primarily used for speed and convenience where a long lasting image was not required as in art prep for printing.
2. The activator solution was very alkaline; as in finger dissolving. ;<) I could take a sheet of film and pass it through the solution and into stop bath without pause and it would have a Dmax of 4+.
3. I see no point in doing this as the material should develop in regular chemistry. Also any paper or film would be quite old. You would also wash out the citric acid or whatever was used to prevent autodevelopment.
4. AFAIK this is not being made today. Someone please correct me if I am wrong.