Updated February 7, 2019 to resolve conflicts when using other sprites in some situations. Added three 1920x1080 PNG basic image templates for you to work off of or use as temporary images until your own map is ready.
One very simple script to bring up a custom map (or other image) when you press and hold "M". This is intended for slightly more realistic uses. Trying to view the map while using other controls will not always work, depending on the combination. As with real life, the best method is to stop moving and then take a look. It will not auto rotate or highlight anything in the play area. Great for exploring and forcing the player to learn their way around by recognizing landmarks, etc.
Image placement on-screen and the "M" can be changed in the script. Simply create your image with the details you need and replace the included image. Please note that the included image is semi-transparent. You can choose the same style or whatever else you wish to use. For ease of use, the included image is 1920x1080 and uses an alpha channel to show only the desired area of the image file, centered on the screen. PLEASE NOTE that this script was created and tested at 1920x1080 and may require modifications for some other needs.
An example map is included.
Original Upload: February 1, 2019.