Finally in the atlas. Sorry for the delay.

Since those above didn't answer this, yes, this is how it works. You can make commercial maps out of the box with the standard license. and those maps can be utilizing any of the assets distributed with the program. Note that this is limited to publishing the maps you make with said assets commercially, you're not allowed to distribute the assets themselves. But please use the contact details provided by Sue above if you need official clarification, as most people here can only give you an unofficial answer.

To add a bit on to what Wyvern said, note that a lot of programs, especially those online browser-based ones, do not allow you access to download the artwork, they only make it available for use within their own application. I don't know the specifics of each of the programs you mention, but it isn't unreasonable to expect they are not downloadable in a legal way, but as Wyvern said, you need to research each of them (or maybe someone here who uses them can comment)

Yea, Ralf only shows some simple editing there, but it gives a good overview of the process needed to manipulate hatch styles. But you can do any operation you want when editing them, including scaling them using the :CC2SCALE: command.

But yea, bitmaps are much easier to deal with.

The technique Ralf showed here unfortunately only works with bitmap fills. This covers most maps, but some maps, especially maps using line-work (like the landform maps) use different techniques for the fills.

It gets a bit more complicated to scale these. I am pretty sure Ralf showed that off in a video at some time too, but I don't remember which off the top of my head. I'll see if I can find a link for a video or something else, unless someone bets me to it.

If you try with for example the Mike Schley overland style, you'll find that this trick works the way Ralf showed it if you use it on a bitmap-filled polygon, like farmland for example.

edit: Ralf demonstrating editing hatch styles in here: https://www.youtube.com/live/-zZGWKT2pN4?si=LOm5YLc6CtJAds-j&t=1187