Okay, I figured it out. These changes will change all radio menus and submenus, the actual communication text between you and ATC, your wingman, etc., and the tutorial text. It's straight green which I think is a good compromise and is highly visible even against white clouds. Haven't tested much but it's a start. This is the end result:
BACK UP ALL FILES YOU ARE GOING TO MODIFY BEFORE CHANGING THEM. I take no responsibility for breaking your game and this certainly wouldn't be supported by ED. I haven't done much testing as I just figured this out.
I modified the following files:
<DCS Install>\Scripts\Common:
'utils.lua' - added a line in the COLOR { section "GREEN = makeColor (0,255,0)":
COLOR = {
WHITE = makeColor(255, 255, 255),
LIGHT_GRAY = makeColor(200, 200, 200),
DARK_GRAY = makeColor(74, 74, 74),
RED = makeColor(125, 75, 0),
BLUE = makeColor(0, 75, 125),
BLACK = makeColor(0, 0, 0),
GREEN = makeColor(0, 255, 0)
}
*Make sure you insert a comma at the end of the BLACK line
<DCS Install>\Scripts\UI
'GameMessages.dlg' - changed every line that was 0xffffffff -or- 0xf5f5f4ff -or- 0x000000ff to: 0x00ff00ff
<DCS Install>\Scripts\UI\RadioCommandDialogPanel:
'CommandMenu.lua' - changed every line with WHITE to GREEN. Also changed every line that was 0xffffffff or 0x000000ff to: 0x00ff00ff
'RadioCommandDialogsPanel.lua' - changed every line with WHITE to: GREEN.
'CommandDialogsPanel.dlg' - changed every line with 0xffffffff or 0x000000ff to: 0x00ff00ff
'CommandDialog.lua' - changed every line with 0xffffffff or 0x000000ff to: 0x00ff00ff
Finally, I saved copies of the modified files to a separate folder on my PC so I can potentially restore them after any updates. This works now but may not in the future.
If you want a color other than straight green, you can find the hex code for that color on the web. Search for HTML CSS Color Online Color library. The 'ff' at the end appears to be constant in DCS. Only the first six digits after 0x need changing. And if you want a different text color for the ATC text, you can substitute all of my "GREEN" entries with whatever. The x,x,x number (0, 255, 0 for GREEN) is the RGB value, also available on the HTML color library.
I know there's a way to include a background around the ATC menus because one of my tests I had accidentally made the whole thing a big green box. I don't remember which change though...