About the prerequisites bug... you have to keep in mind this is a hardware limit. To allow combinations of prerequisites, the only easy way to store them is by using single bits. A 0 for "Not A Prerequisite", a 1 for "Is Prerequisite".
But that way, you can only store 8 buildings into every byte, and a normal big value in 32-bit programs is only 4 bytes... meaning you can only store 32 options. So it's normal that they had to make choices in which buildings to add to that list.
As for the Nod EVA, I think maybe the easy way to do this is simply by making a duplicate EVA voices list, and making the EVA playing function check the current player side, and decide which list to use depending on that. It would mean I don't even have to expand the normal list at all; it'll just be a duplicate with the Nod filenames

The naming format should be easy. All GDI EVA files end on either "1" or nothing. All Nod ones will thus, logically, end on "2", keeping the DOS 8.3 format in mind (so UNITLOST.AUD becomes UNITLOS2.AUD, and not UNITLOST2.AUD, since that's more than 8 chars in the first part)
And yes, I have made a custom editor (well, I adapted an old savegame editor to serve as C&C95 editor).
I probably won't actually make my own editor, unless I remake all units, buildings, structures etc sections to make sure all compiler-optimized values are expanded to their actual possible size. For example, if you got a unit with less than 128 health, it's now stored in 1 byte instead of 4, while units in general CAN have more. This of course prevents you from giving it more health if you mod it, since there
is only one byte to edit. So if I remake the sections, I'll make sure all of these are expanded to the full 4 bytes.
This does have the disadvantage that all current editors would become completely incompatible with it, so I'm really not sure if I'll ever do this (not even counting the fact it's a crapload of work)
This post has been edited by Nyerguds: Dec 7 2009, 10:48 AM