I can relate and understand your frustration autobahnshine, one thing about Zymol products is that you have to know and follow the process down to the "T" no dviating if you do it will be a pain to work with.
I too made the mistake of applying Concours on the entire vehicle and left it on for a few minuets and boy was I cursing lol...Vintage has been the only one that I've found that you can leave for quite a bit of time on and you wont have a problem with...mind you I haven't used the entire line up of wax's that Zymol offers just a few but out of all of them Vintage is the only one I've found so far to remove easy over night.
As for Swissvax Concorso, sorry I can't comment as I haven't used it but that will be changing very soon