There are a lot of questions and issues with the information contained in FamilySearch.org's Family Tree program. Most of the functions of the programs are adequately covered in the Reference Guide. See Using the FamilySearch Family Tree: A Reference Guide (18 October 2013). In addition, the FamilySearch.org Blog contains valuable updates of new features added to the program. See FamilySearch Blog. For example, a blog post on 18 April 2014 had the topic of a "New Way to Move a Person to the Main Position on a Fan Chart." In addition, I try to keep up with the changes when they are major and affect the way the program operates.
But most of the issues that come up from day to day that involve the data in the program rather than its operation. How do we resolve those issues? For example, what if two researchers in the same family have different ways of spelling an ancestor's name? Or what if two or more people disagree on dates and places? These types of issues are inevitable given the nature of genealogical research and the state of the historical record. The key here is to contact the people involved in making the changes and request source information substantiating the changes. If the person refuses to respond or does not have an email address, then edit the change and see if the person returns to make the change again. Repeated changes without source information or failure to respond or lack of email address should be reported as abuse. Here is a screen shot showing the link to report abuse:
The most common issue I hear from patrons and missionaries at the Mesa FamilySearch Library involve names that change to people who are completely different than the actual ancestor. In other words, an ancestral name becomes something entirely different and the surname does not match. This may possibly be caused by merging individuals who had been combined with the wrong individual in New.FamilySearch.org. However, this also might have occurred because someone deleted the correct individual, substituting the wrong one. Be aware that this issue does not mean anyone in Family Tree needs to be deleted. These issues involve relationships and editing issues not deletion.
I suggest a two step solution. First, search for the correctly individual in the program. If the correct individual is not found, then he or she may have been deleted. Carefully examine the Latest Changes and all of the previous changes. You may simply be able to restore the change and take care of the problem. Here is an example of a Change List showing the Restore links:
If this does not work, then search to see if the correct person is in the program. At this point, the issue is that your relative and siblings are not the children of both of the parents showing in the program. You can then continue the editing process by deleting the relationship of each of the correct children from the incorrect parents. Remember, if one of the parents is wrong, then the child is not the child of that relationship and the relationship needs to be deleted. Do not delete the individuals, only the relationship. See the Reference Guide above for specific instructions.
One very good idea is to be sure to write down the identification numbers of each child first, so that if the child disappears, you will be able to find them again. then add the correct parents as parents of the children. Do not delete the "wrong" person as this will cause even more improper relationships.
Almost all the other problems with Family Search involve the same or very similar issues. I constantly hear complaints about "wrong" information in the program. The people making these complaints have almost never made the corrections to the program. Sometimes they are embarrassed at how simple it is to correct inaccurate information.
One type of information that causes consternation involves problems with the way the program does or does not show living people. Although living people can be added to the program, if these people are members of the Church, they are duplicates. Further, the living people can only be seen by those having a direct relationship to them, usually only the person who entered the information. If you find wrong information about living people, including yourself, who are members of the Church, then these errors reflect errors in the Church Membership program and need to be addressed by contacting the Ward Clerk where the living people reside. Obviously, this can only be done by the person involved.
As with most of the problems with technical subjects, the answer usually involves reading the manual.