this happens in rebellion as rebellion no longer understands the galaxyforge mapversion3 maps, it only understands mapversion 4, AND does NOT look at the mapversion before trying to read the file. it did understand the mapversion3 maps in 1.01, but the map reading was changed in 1.02 for some reason, and yarlen is looking into this.
and I am in the process of updating my map updater to update all maps in the rebellion mods/maps/saves area to mapversion 4, but at present the map updater is only updating approx 90% of maps properly.
harpo