I'm modding my game's UI into a dark themed UI. I started with ProGen's UI and managed to remove most of its Vanilla-ZH blue borders through the MainMenu.wnd file and changed the buttons' background through the shell interface targa file. The problem is I don't know which .wnd file and where in that certain file can I edit the border color of popup tooltips such these:

popup tooltip where it says "USA Campaign"
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popup tooltip for Music Volume in the game options menu
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popup tooltip for factions in skirmish menu
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ShockWave has these tooltips with a black border so I tried copy-pasting their window settings, but for some reason, MainMenu.wnd causes an error and both SkirmishGameOptionsMenu.wnd and OptionsMenu.wnd from ShockWave did not change the border colors for my mod. I'd still like to keep the Worldbuilder button in Progen's main menu, so I'd rather just edit the tooltip borders myself, but where and which file(s)?