How can I change the photo that appears as a thumbnail for the Album?
How do I change the photo that appears as a thumbnail for an individual? (In FTB I can tag a photo as a "personal photo".)
Can I reorder the photos in an album?
If I want to update the tree on the family site by importing a gencom (I haven't succeeded in publishing from FTB) to replace the tree that's on the site, will the site remember the individuals that the photos are associated with?
First of all, yes you can order the photos of an album and that's actually how you change the thumbnail for the Album!
To do that go to Photos>FInd>choose details view from the top>Edit>contents and there you will have the option to order your photos. In the order, the picture at the top of the list will appear as a thumbnailf for the Album.
To change the photo that appears as thumbnail of a person, if you are talking about an FTB tree then you need to change it from FTB and then republish. If it's an online tree then choose the person from the list and go to info right below the person's picture you will see clear personal photo. Choose this and the the picture will be removed from thumbnail and will stay in the list of the person's photos and then the next picture you add will be the personal photo.
As for importing a gedcom, when you import a gedcom to the site it will not recognize it as an update but will be a new tree so will not remember the photos that are associated. So the best way is to publish from FTB or to work online all the way through. If you could explain the problem you are having in publishing the tree from FTB then maybe we can come up with a solution for that.