594 MB update, apparently made by HexaDrive. I've played ZOE2 up until the battle with Leo and it's very smooth so far. If the rest of the game is similar it'll be the best version of the game easily.
Wow, this patch makes a world of difference. They did a hell of a good job.
Without sitting down and doing a full analysis, here is what I've noticed in ZOE2 (haven't tried the original yet)
1) Framerate now operates at a stable 60 fps making it much smoother than the non-patched version as well as the PS2 original. Only in the most extreme circumstances does the framerate dip and those dips are extremely minor.
2) Post processing anti-aliasing appears to have been added resulting in extremely crisp and clean image quality. The original release did not use any sort of anti-aliasing.
3) Particles effects are now rendered at full resolution. The PS2 original used low resolution particle effects in order to maintain decent performance. I cannot actually recall if this was also true of the initial HD release but I can confirm that particles are rendered at a much higher quality now.
Those are the primary changes and they completely transform the game. The entire snow sequence operates at 60 fps a good 99% of the time providing a faster, smoother experience than even the original release. It feels remarkably good.
I'm also interested in examining the textures as the ship interior appears to be extremely clean and sharp in a way that I would not have expected from PS2.