Unable to delete uploaded photos

The Meural is perfect for a slide show…but it requires ALL PHOTOS in the upload setting, not SELECTED  PHOTOS.  Why?

So it uploads 500 photos, when I wanted 10 for my slide show.  Why?

I try to delete 490 photos, but they are LINKED.  Why?

Can’t unlink, unless I resync, but I need to delete all the photos in my source to resync and keep the 10 I wanted for the slide show?  Seriously?  I must be missing something important.  I already spent an hour wading through info that helps me buy new products, but not enough info to make what I have useful to me.  Why would I buy more from Meural or Netgear?

Please fix this bad programming.  A simple edit/choose photos/delete would be extremely helpful for a lot of users, and being able to choose single photos to upload instead of all photos should have saved having the problem in the beginning.