FamilyTreeDNA doesn't handled preferred names. They use the first one in the file. I've contacted their support about this and they said they were thinking about it.
I had to create a special ancestor-only tree for my direct lines and remove all names except the preferred ones before uploading to their site.
Rosemary
I had to create a special ancestor-only tree for my direct lines and remove all names except the preferred ones before uploading to their site.
Rosemary