There are four possible options:
1. Strait Editing - I highly recomend you don't go with this option. While it's always possible to program a file, even the EVN dev team used something else.
2. Nova Tools - You can download this from w00tware's website and it is what was used to create EV Nova. Can't get much better than that. You need ResEdit to run NovaTools.
3. EVONE - EVONE is supposed to be a bit better than Nova Tools for novices, so you may wanna go with that. However, at higher levels, it can be very powerful too.
4. Mission Computer - Mission Computer works pretty well, there are some weaknesses in using it for more powerful aplications, but it should be fine for what you are looking for.
Personally, for a high end plugin, I'd recomend the last three options used in concert. However, you really only need one for what you are trying to do.
As far as manuals go, use the EV Nova Bible, which can be found in the Documentation folder of the EV Nova main directory.
NB: If you are on a PC, then you will need to use and emulator.
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