Are these the correct paper dimensions?

[Einhander]

11.11 by 7 or 6.985 by 11.0511

I saw 2 different youtube videos and they say that the media cases have gotten smaller.

Also should it be scaled to 98.5 percent and all 4 margins .5 inch?

[Arseen]

That difference is so minisculke that it does not matter.

All our covers are correct size (unless DPI failure but then the whole covers is way off as in 3 times too big).
At worst you must trim a bit.

0.5 inch margins (5mm) apply to A4 size paper.
With Legel size aper the margins can be bigger.
Letter size paper is too small unless you can print truly borderless without any margins, and even then you might have to scale down a bit which fucks the image quality.