Thanks Joe, in fact, I don't know why I did not test it yet, but indeed normal shift select works on the desktop Photos. Does not work though in icloud.

Everything going great, but I don't think Photos on desktop will resolve, pessimistic; will wait a couple of days, but it seems of whack, showing a lot of deleted photos. So.. wait a day or two and the... I could just copy the laptop Library right over to the desktop?

And Final: When it's all synced then if I delete a photo on one, it will sync all others: laptop, desktop, iphone and icloud?

Hence no need to open and log into icloud.com?

BTW, any idea why the desktop library has old photos, Maybe it got frozen?