The Adobe Flashplayer, iirc, has had three serious problems already this year!
Like the OP I couldn't work out how to get the 442 version onto WATTOS R8 and this post may be of
no help at all since I have given away the R8 computer and can't remember how I left it.
As it was a slow machine - Flash was next to useless in FIREFOX, anyway.
IIRC, 1 option is to block Flash with the FLASHBLOCK add-on and to download the clip to your hard-drive with the FLASHGOT or DOWNLOADHELPER add-on: you don't have to wait for the download to complete before you start watching.
Going to
https://www.youtube.com/html5 allows you to flip between the FLASHPLAYER installed
and the HTML5 player as default - the default varies from browser to browser.
IIRC the default for MIDORI is HTML5.
Apologies for the vagueness of the post - but I was fiddling around with FLASHBLOCK,
GNASH/ADOBE, blocking/activating SHOCKWAVE via the PLUG-IN option in ADD-ONS
(all without really keeping track of what I was doing). DOH!