Will the new 2020 skins also work using the 2019.0.14 release?

I attended the special event last week (besides: it was a fine showcase for all the overwhelmingly great new features!), and since then I was playing around with my 160+ topics RoboHelp 2019 project in the 2020 Trial version. Great fun, even though I didn't even test the new Review process and creating sophisticated PDFs with that new tooling!

Of course, I started the purchasing process already within our company (worth every penny!!), and also for shifting RoboHelp to macOS in a private license of TCS which I'm about to make use of for my upcoming Master thesis.

Now that we're about to start a public survey on our RoboHelp content, I was wondering: would it be possible to transfer the two new frameless skins (especially the top-menu version) to use it with Rh 2019.0.14? Or is there so much altered JavaScript in it that it wouldn't work?

By the way: I also was wondering how to utilize the spaces on the left and right in the top-menu skin, where the panels had been previously.

If we change to that skin later on, it would be for the greater topic width that allows for large tables and schematic drawings to be visible without scrolling. By now, on my first approach of generating an output with our data from Rh 2019, the topic width stays the same leaving the space of the panels just blank.

Did I do something wrong in the skin's settings?