I'm new to NM as well, use it now about 3 month, switched from Mindmanager after using that for about 10 years first on Win later on Mac (the actual Mac version disappointed me to much).
re 1) Lack in support? Don't see it, I had some questions in forum and got answers fast. I addressed some requests and suggestions to service, response was in acceptable time frame and good qualified (and I can really compare it to MM, where I opened some requests this year). Maybe there not so much entries in the forum, as the users don't have a lot of problems? Have you found http://www.novamind.com/connect/
, there seems to be an active community as well. The only topic at the moment it's not adapted for NM5 yet.
re 2) Didn't experience this in any negative way. I have some bigger maps without any negative impact. I prepared those in the VM in NM5 for Win as presentation, it works very well. The other SW, I used, supports presentation with the actual version, needed for the same map about 15-20 seconds to switch from 1 slide to another (reply from service ... nothing qualified).
So I like NM and so far I'm happy with the change. Now I'm waiting the Mac version comes over the time delay and we Mac users get the missing functionality from Windows version (and I have not to use the VM any more).
I think Gideon and team did a fine job and I like that the responsible persons of the company are reacting in the forum.