I can't seem to get zMUD's built-in mapper to work correctly. I've tried using the built-in auto-configure (which didn't work), then editing the configuration to support things like changing room descriptions and multi-line exits. For some reason, the map will always follow me for one move in any direction, and then freeze and not recognize any further movement. If I reconfigure or change any configuration settings, it will follow for one room again, then stop responding.

Could I have some setting set up wrong, or maybe it's not identifying my prompt properly (even though it auto-detects it)?

The automapper doesn't work as well for IRE games as it does for many other types of games. You need to make certain triggers and use the automapping script commands to tweak the performance. Even then, it's somewhat of a pain to get everything working reliably. This is why people (such as myself) are able to sell the knowledge on how to configure the automapper.