All existing footage of the Titanic

Hi all,
I'm very sorry to be posting a question I am sure has probably been posted before, but could someone please confirm that this clip contains all existing footage of the Titanic -
and confirm precisely what is happening in the clip? and when it was shot as I have heard conflicting opinions on this..?

As far as I know it is 3rd of Feb 1912 (i have also seen the date 2nd of april 1912 or even various dates in 1911 being attributed to the clip) - the Titanic in Thompson Graving Dock in Belfast about to be towed in to the outfitting bay in order to have an enclosure added to the promenade deck. How much of this is correct? Is there any additional info?

I have been informed that there exists footage of the Titanic at an earlier stage in her construction but can't believe I am yet to come across it.

Any help would be hugely appreciated.

Thanks in advance!
The second photo down on that page links to the file which shows the Titanic being nudged into drydock. As far as is known, it is the only surviving motion picture footage taken which actually shows the ship moving. If any others exist, they are unpublished and in private hands.