I downloaded and played the Alpha Release just now. It acted just like it should. No broken files.
The engine's name is NakaSMK (combination of my pixel perfect idol, Yuji Naka, and the "SM&K" initialization string used in Sonic & Knuckles), and is the file Sonic2HD.exe. That is the portable part, takes care of graphics, input, sound, file I/O management, and the user interface. See it as the Megadrive/Genesis hardware.
The game is all run from S2HD.DLL. That is the cartridge. To have more than one cartridge, and to connect them (locking them onto eachother) is a possibility.
The physics can never be 100% like the original. The game is based off Sonic 3, with some changes "for the good" to limit some actions to Sonic 2. But it is a complete rewrite of a rewrite, more closer to something you would see in New Super Mario Bros DS/Wii/Mii. The key rule of the engine and game is pixel perfect movement. I have several proof that Naka had this rule when he first created Sonic, and throughout his Sonic engines.
Some this to note about the background:
The background now has the mini clouds that were originally in the design of EHZ (as seen in the earliest mockup).
The background uses the best implementation of original Sonic's technology, which is from Sonic 1 Version 2's Marble Zone and Scrap Brain Zone (but not Spring Yard Zone, hehe)!
The technology also uses a very cool thing from Sonic Advance 2's Music Plant, which was only used there, and never reused, BUT totally kicks ass, especially performance wise.
There are minor chanages in the level design. Some of them are forced, because of the data used is not 100% like the original. Some objects have been moved. Most slopes are generated with higher precision and real angles instead of being hand made like in the original, thus the experience you feel is a little different. I do agree that while some choices made things better, others made things worse. But there is no way of doing everyting perfect, as if you push something in one direction, alot of other things fall apart. Finding the right balance is a hard job of days and sometimes weeks. If you look for bugs, you will find bug, and that applies to original Sonic as well. Please remember what an Alpha version stands for.
I'll try to upload a smooth gameplay video within the weeks that follow. It is too early for me to show gameplay from my point of view (I simply have too much to show and talk about).
EDIT: Oh, did you all see the PDF file? I do love game manuals. I'll have to print this one.
This post has been edited by LOst: 28 March 2012 - 01:13 AM