Tile Renderer is a MaxScript from Chuggnut that renders image sequences to a tiles bitmap within 3ds Max. It's mainly used for fonts in games, taking a sequence of images and outputting them as a single tiled bitmap.
There's one important note for correct output. Safe frame should be left off, because a render with safe frame on will not come out at the right size. The developer believes this is a MaxScript bug. Following that guidance keeps your tiled bitmap at the expected dimensions.
The current version is 2.3.5, and it's listed here as free. You can find the tool on ScriptSpot, and Chuggnut's developer page at chuggnut.com is the place to check for the latest build and any licensing details.