No, Alister means reflexives. There are things in the meta data that need to be changed from level to level. It is harder to rebuild xbox maps 1) Because all of the cache files need to be 47MB, so to add something you must delete something, and 2) There is currently no program such as hmt that will rebuild the map for you.
Map rebuilding isn't a program, it is a process of adding all of the things you need for something, say banshee (model, coll model, fuel rod, etc), not to mention changing all of the reflexives and a few other things. It would be possible to make a map rebuilding program for xbox, but currently there isn't one. So, you CAN rebuild xbox maps, you just have to do it by hand

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If you have no idea where to start, I recommend that you start reading forum posts and tutorials. Most of the really good modders are self taught, im sure you wouldn't find them posting on every little thing they didn't understand. Experiment with some things, and read some tutorials. If you have any questions, there are a lot of great modders here that are more than capable of helping. All I'm saying is do some research before you start asking about thinkgs that you will know were stupid questions later on.
You might want to talk with Allister about this. It's a lot easier to split the work load when working on big mods
