We differ on the the definition of a fatal error. If the program is screwing up my database I consider that a fatal error.
However there are many people including me who are successfully using FTM 2012 for the two years since it came out.
If you were willing to share SPECIFICS on when, where, and what you are doing when the problems occur; I know there are people here who would be more than willing to assist in resolving you issues.
The first thing that comes to my mine, if your problems are syncing issues; is the reliability and speed of your internet service. If you are usinng a dialup, or have slow internet connection and a large FTM database, you have the prime set of conditions for sync problems. If the connection is is slow and times out frequently, you will have issues.
If the internet is not an issue, the next thing would be, do you routinely compact your database. If so after compacting is the decrease low <1%.
If you have attached media where is it located, and is the directory always available to FTM.
Have you downloaded all of the available updates for FTM 2012. My copy has been fully updated and shows Version 188.8.131.523 (PC) when you click About Family Tree Maker from the Help menu.
Have you resolved the errors that are shown in an error report. Publish, Person Report, Data Error Report, (Note you must fix them individually.) I unchecked the obvious errors like missing dates, etc.
Your problem can be solved with patience and communication.