Well, good for you, who develop on FDM, if there are 'fans' out there, who even in case of such a job as the so called FDM 5 Alpha (me also name this a pre-Alpha - if ever) sound really optimistic.
Sadly I can not share this optimism in the view of a program, that is supposed to represent the next generation of FDM and lacks several good features of FDM 3.X.
How do I have to interpret this step stone? Going back 3 steps in order to make forward 2...?
A further development should consider to enhance features which are in a wide spread use instead of removing them, my opinion. Then... instead of resolving the errors in the old version making a completely new one can be a good solution to circumvent buggy code, which is undocumented. But... was this really the reason? I can't believe that, sorry.

In short: FDM 5 didn't work for me more than 3.9.X and as a result I'll going to circumvent FDM as long as I can't read many good news about it (because then there will be more users - and not only its 'fans' - who judge neutral instead of you away-with-the-fairies 'fans'. ).

Good bye!