I red some strange issues on the forum (example:
https://www.playonlinux.com/en/topic-16367-Configurator_has_eternal_spinney.html ).
I think that a simple way to help those users is to "reset" the settings of POL v4.
Is it documented somewhere ? how to do it the best way ? (the less destructive)
(If I get answers, I think I will add this issue to the wIki).