Disclaimer: This is a CUSTOM build of MapTool based on MapTool 1.3.b87, and is delivered AS-IS. Its build number is 1006. Its VERSION is "Rumble Custom VI." It is NOT endorsed by the MapTool development team, it is NOT an official build, and it is NOT supported in any way. I may from time to time issue a new version based on a more recent build.
DO NOT POST BUG REPORTS ABOUT THIS BUILD. USE AT YOUR OWN RISK.
Okay, so, that said: I've got a custom build of MapTool - it's called Rumble Custom VI - that I've made available to the GM of the game I regularly play in, but thought I might as well let other people know in case they want to use it (and in case they are "power users" who want to experiment, basically). Note: You will get a warning when loading any campaign from an official build into this, due to the version being what it is. It should not prevent proper campaign loading. If you save your campaign in this, and you can't subsequently get it to open in an official build, well...them's the breaks.
Version
This build offers two custom features:
Line of Sight Tool: The tool allows various kinds of line-of-sight checking. It is primarily useful on square grids. It may not work at all on hex grids (that was part of the reason it never went into the official build; I couldn't get it to work on hexes). Note that this functions like the ruler tool - it is only visible on the screen of the person using it (it doesn't show for everyone when one person uses it). To use it:
1. Select the tool and click on the starting corner.
2. Hold down Ctrl to select a single square in the target's space, Shift to select the full-size target, and don't hold down anything and you'll just get a single line.
3. You can select a different corner by going back to the starting token and selecting near a different corner. The sightlines will adjust.
4. Click on the map to clear.
Instructions also show in the status bar at the bottom, as usual.
Here are some screenshots: