I forgot to reply to this completely. Thanks for implementing #1 and #3, that works great!

I found a new bug though: If you use the @ in your filename, it skips lines and blends with your other options: https://i.imgur.com/4cmLsZv.png

For #2 I will still want to still strongly advice to move the folder name to the top, because:
1. This is very much in line with how the file explorer works for home computers and what people are familair with.
2. The context of the bottom right corner changes and is different than any other menu screen standard, which I don't really like. This confused me because it's somewhere you only look when not really familiair with the option given. For any other screen gives extra context, most often being a description of the selectable actions, such as: "Choose game type", "Choose connection", "Press enter to start". The only odd ones I found are "Main Menu" (but I understand main menu doesn't really need a description), "Players on this computer" which should ideally be "Set player amount", "Video options" which should ideally be "Set video options" and "Active server list" which should ideally be "Select a server". (The fact you can see them, makes it kind of obvious that they are "active").

As for "Select a Level" in HCL, going down a folder doesn't really change that you well... still have to select a level. I like to emphasize again that in no other menu step it's ever required to look in that corner once you understood the menu step. After playing jj2 for so long, I frankly even forgot there was text there.