I have received the latest firmware update on my NOW 4K Smart Box and totally agree it is now so slow and sluggish navigating around the UI.
I also don't like that NOW have removed the bottom grid row with the tile boxes such has My Account etc.
To access My Account since the update you need to highlight and click on the gear wheel icon towards the top corner of the screen, but all the gear icon really gives you is My Account option and not the Settings option where you still have to use the hidden LHS menu by pressing the back button on the remote.
For me pressing the back button when on the home screen still brings up the hidden side menu on the left hand side on the screen including settings.
Don't know why it is not working for you, perhaps try a forced software update by pressing the Home button 5 times, quickly followed by the Fast Forward button three times, then quickly followed by pressing the Rewind button twice.
Oddly I could access the menu this morning, but checking updates said nothing changed since June. That's obviously incorrect as the ITVX app has been added recently & I certainly didn't have these issues until recently. I wonder if there's a connection?
But sadly I decided to try a factory reset & now have the same issue as many others here, in that I can't complete setup & have no home screen at all. 🙄
I’m having issue in that settings look like my account settings rather than other settings. When I’m in there it tells me to go to home/settings/ audio but just going in circles. Reason I wanted to look at settings is because my sound is lagging - lips are moving but speaking delayed. I tried switching off including removing roku stick which didn’t work so even tried rebooting router but still the same. So assume this is all connected to latest update too
There is a new firmware out (version 11.5.3 build 4077 -68) for my NOW 4K box and I have just downloaded it under Settings > System > Software update.
It seems pretty fast (noticeable difference for me) when navigating around the NOW GUI, but I haven't tested properly yet for any bugs or glitches.