I might not understand your problem.

Assuming you are referring to uploaded videos, I've just added a video, deleted it and added it again. No problem at all.

Has the video you had deleted still in the conversion queue or are there any videos in the queue waiting for conversion? Maybe that's causing your problem. You should check the queue on the corresponding tab on the iZAP Videos settings page and empty the queue if there are any (invalid?) entries.

I have no other idea at the moment that would explain the problem or any hints how to fix it. If it's not the queue you might want to describe in more detail what exactly is wrong. Maybe I can reproduce it with more info.

Note; These are Off Server videos.

I've narrowed it down. Doesn't appear to be any problem after all. It appears to be localized to my installation.  As I upgraded elgg along the way from 1.+ to the most the most current elgg 2.3.4, and from the original iZap Video to your IZap iionly Video version, there were a number of videos that must not have converted properly and thus did not work. So, I would delete them and reload them from YouTube. But they would not reload, as I explained above. But this only happens with the specific videos that were already loaded and seemingly corrupt and I'd try to reload. In summary, this problem only happens with already installed YouTube videos from the past and current reloads. Therefore there are a number of YouTube videos that I will never be able to use. 

Note, there is no problem if a I load a YouTube video, delete it, and load it again. This works fine. The problem is only with old videos. 

And, I've only got a few dozen of these videos, so I'm not going to worry about it, unless you can think of some easy fix. 

Thought you might like to take a look at the error message I get when I try to reload one of these problem videos. This error message is a list of all the fields that should have loaded with the video, but did not. There was no other message or indication why the error occurred, just this...