A patch instead of a replacement is the recommended way to do such changes. It is much cleaner and does not alter the original authors release (very important).
Good sentence structure makes your reviews easier to read. Personally I'd rather read it paragraph-by-paragraph as opposed to one giant blob of words. My suggestion is put more spacing in between your numbered suggestions.
In general, the map is famous enough to describe its design and playability in details. It's good for duels, FFA (up to 4 players) and TDM (2x2).
Bots are not supported.
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So, here is a link to the archive where I tried to fix something.
speedy.sh/raf8x/ztn2dm2.pk3
1. I added missed sound, ztn2dm2.aas (so, now bots are supported).
2. I replaced old textures with high resolution ones.
3. I added FFA and TDM into ztn2dm2.arena.