I purchased this SW several months ago and have had nothing but problems since installing to my MAC currently on MAC OS X 10.7.3. When first installing it was fine. I manage 2 Ancestry online trees and planned to use FTM2 primarily for the chart and report features and make all my changes in Ancestry; both my trees imported and sync'd in FTM2, it all went fine for a few days then problems. After a successful sync in FTM 2 as indicated by the message, however the status indicated my online tree's and FTM2 where not sync'd yet the message indicated the sync was successful.
I broke the link using tree settings in Ancestry and then deleted my 2 trees from FTM2 successfully. I then re imported the 2 trees from Ancestry again and the Sync worked. A week later same problem; after what appeared to be a successful sync message showed both trees had changes that were not sync'd.
I contacted Ancestry who responded that I could have had a bad install of FTM 2 on my MAC, I backed up my Ancestry tree and FTM 2 trees and went through the uninstall and reinstall of the SW no issues. I then imported the trees to FTM 2 from Ancestry and sync was working I was feeling good getting through a whole 7 days then 15 days and yesterday same problems again.
I am sure this is a SW problem and not FFS (fat finger syndrome) message boards seem to indicate some problems out there but mainly with windows versions.
I welcome constructive feedback, meantime I will park the issue and not use Sync rather I will use FTM 2 as an additional backup by importing online trees when i need to run new reports.

Update 17 April. When opening FTM 2 this morning the message indicated that neither of my Ancestry Trees were linked with in FT. The Web Dashboard told a different story indicating the both trees were linked. The only was to fix this is to break the link via Ancestry 'Tree Settings' and to relink the trees.