I am trying to add video to my email using the video block. I get a message that the video is not available, check back later - but when I test the link, it works. Then, when I re-do it, it says thumbnail not available, check back later.  Again, the test link works.   Anyone else having this difficulty - could definitely be "user error" as this is the first time I'm trying this....any help is appreciated!!! ... View more