There's a new release of the Aleph One build at the Marathon Open Source site. The highlights include:

...MML support for lots of previously hard-coded properties, such as control panels, faders, liquids, items, platforms, and scenery objects. In addition, Marathon no longer restarts sound effects when you switch to and from terminals and the map view.

NOTE: MML refers to the Marathon Markup Language, an XML variation used to configure variables in the open source Marathon project. Skip on over and pick up the new version from source.bungie.org's latest build page.