Damn, I really don't know what to say about the Lost Alpha. With full access to game sources, seven years of development, lots of good developers, agressive marketing everythere and users donations, they've made the ultimate S.T.A.L.K.E.R disappointment EVER
First of all, it's buggy as hell. Everything what can be broken is broken, what can be spoiled is spoiled. Whom the hell are they allowed to make changes in game engine? This is awful, they even somehow manage to broke the NPC's combat AI. It's now absolutely braindead, even in the original game it was so bad so I written myself a full-scale standalone scripted combat AI for OGSE 0693, but AI in LA is even worse than in original game. They've managed to step on a rakes even in game's dangers recognition and NPC states manager, which problems are well known and documented by many dev's including myself.
Second, they heavily oversized the locations. There are absolutely nothing to do on them, yes, i know, users wanted a bigger locations, but not so big ones.
Third, the plot is awful. Illuminati in my S.T.A.L.K.E.R? You must be kidding. Who wrote the plot, an UFO freak? They don't mistaken the game they are modding? It's S.T.A.L.K.E.R not DeusEx, you know.
Fourth, gameplay features are bleak. Really bleak. Does they really think a PC with tetris game at barmen's room can add some joy to the game? If they really wanted to do this, they've must add at least a hacking minigame to this. All this things added was interesting 4-5 years ago, not now.
Last and worst - what is so special about leaked build? Are they some A+ game gevelopers or someone? We have some builds leaked then we was in process of making OGSE 0692, and just warned the users what leaked build are unfinished, unacceptable by our standarts, and by distributing and playing it they will spoil their own enjoyment from game and mod, and we wouldn't provide any technical support or feedback on this build. And then we just continued ours work. And everything went fine in result.
Verdict: goddamn disappointment. I've, being a game mod developer, waited LA myself to see and play, hoping to see something revolutionary. Well, I've seen a revolution as result. A revolt of bugs and nonsense in a simulator of homeless tramp in the industrial wasteland. Facepalm...