Hi, @NRKorsakov. The Applications Palette is configurable, but it doesn't appear that you can add favorite folders. For more information, see: Applications Palette [Keyboard Maestro Wiki]
You could certainly create you own palette to add favorite folders. Keyboard Maestro palettes can be launched in a variety of ways. For more information, see: Palettes [Keyboard Maestro Wiki]
If you'd like access to a set of favorite folders via the keyboard, you might be interested in a macro that I'm currently developing. For more information, see: Want to Help Test a Finder-related Macro? - Questions & Suggestions