I'm pretty sure that forum member (there was a url link here which no longer exists) (Bert) uses FabA EW for alt-processes, but not sure for pt/pd. you might want to shoot him a PM to ask
I am not sure if Pt/Pd can be done over Gum but I think gum over another process other than Cyano might just be the issue (not chemically proficient enough to be a guide sorry).
I'm pretty sure that forum member (there was a url link here which no longer exists) (Bert) uses FabA EW for alt-processes, but not sure for pt/pd. you might want to shoot him a PM to ask
I use Fabriano Extra White often (I like it). But I've never made pt/pd prints yet. (Would love to learn though).
I like the Extra White better than the White version, for the White version is a bit too yellow to my taste (unless you want a warmer print).