Dear Fellow Hobbyst:
Greetings to all! Thanks very much for all your answers and comments. I really appreciate your support. So here are the responses to your queries and comments:
A. Before I primed the figures, I did let them soak in a bath with dish detergent for about a day and then rinse them carefully and let them dry for another day, before I started applying the prime.
B. The prime is peeling as well as the paint.
1. Figures: Soft plastic - from Airfix, Revell, ESCI
2. Priming: With ModelMaster Prime, in white, gray and plain.
3. Colors: For all of them Tamiya Acrylic
Once again allow me to express my gratitude for your comments and suggestions.