My sincere apologies for the delay in getting back to you, we are currently experiencing a spike in our support volume.
After consulting with our dev team, they have confirmed that this is the currently expected/proper behavior for the annotator. Nonetheless, I tend to agree with you in that there is inconsistency between text vs rectangle annotations (where text disappears, rectangle stays) and wish to investigate further into whether this is actually the ideal way. I have created this entry
in our public Feedback Portal for you to follow the progress of this issue.
As for the video, it may be available here
(or one that is similar), however I will have to get back to you with regards to whether a higher quality version is available.