I've tried reinstalling both maps, but it still comes down to replacing the object files. If I keep one set, the others object(s) are not visible.
Cloudfish, if you're asking about the .fho files, the ones conflicting are MyPlants, MyRocks, MyTrees, and Miscellaneous. Only one of the maps has the Default .fho, so that one is not conflicting. [They all only work if placed into the my_objects folder, they don't seem to get along with exports.]
If you're talking about the custom meshes in general, I know most of them are Hammy's meshes [a few of the dens, logs, plants, shrooms, plants] but I haven't found the others yet.
I'm not sure who the deadtree is by either; I was given the download for it by the mapmaker.