I find it incredibly frustrating that this game was originally released on armorgames.com almost a year ago and it doesn't appear to have made any progress. If you've fixed and improved upon the game as the steam updates would suggest, then you do yourself a huge disservice uploading a year old demo on a major website like newgrounds.
That being said, there are obviously major flaws in the game, things that, frankly, I'm surprised were even allowed into the game in the first place. Forcing players to advance after a set number of waves and miss out on loot and potentially abandoning dying survivors, that is just sloppy thinking. It happens so frequently in gameplay (everyones gameplay, judging by the reviews) that it almost feels like the devleopment team didn't even play the game. I would rather have seen one long linear level that you advance through at your own pace; you've already proven that is a possibility in the way Exploration missions are handled.
Like everyone has mentioned, the loot setup is garbage. Granted, it's an alpha, and there's a clear "coming soon" over the supply icon, so hopefully there are plans in place for that to make some amount of sense.
I would agree with some other reviews on here, the survivor stamina is bullshit. It takes around two to three days to clear a location 100%, and an additional day to travel there, but the very first time you visit the location you will loot everything, and the subsequent days offer nothing in return except killing zombies (and experience, I suppose.) There's no incentive to do this aside from fuel, but honestly I've had more luck finding fuel on accident than I have from completing missions and missing out on food. This is a balance issue that I'm hoping is fixed in the future.
Another thing that I think is shitty is protecting the survivors. I am not against it as a rule, in fact I think that it makes perfect sense, but the way in which it's executed leaves room for flaws. The survivors, after saying "save me!" appear to run in a random direction, instead of towards the group or behind cover. I watched a survivor run directly to the rightmost edge of the screen and camp on the zombie spawn tiles, leaving me no option but to lose the survivor or put my team in SERIOUS danger and stare death point blank in the face. It doesn't make sense. And once the survivors pick their spot, they don't move, which meant surviving 4 waves of pure suicide.
I don't understand the left and right clicking decision in Flash. I appreciate that you got it (sort of) working, but I feel like it leaves a lot of room for errors and fuckups. Numerous times my controls simply stopped working and I was powerless to direct my men in any direction. I feel like right clicking is better left to Unity. In fact I wonder if this entire game wouldn't be better done in Unity, but that isn't my call to make, I'm not the developer.
That being said I am HOPEFUL that this game improves in major ways, because the concept is strong and I've always been a fan of the infectonator games, but there were some very major missteps in this alpha. It's nothing more than a proof of concept at this point, and judging by the reviews I'm reading it's doing more to turn people away than it is to convince them to sink 12 dollars into a game that's unplayable.