Well to be honest with you, I haven't had the chance to try out the annihilation beam, since I kinda rushed through the demo. I missed two upgrades : The Time Suit, and the previously stated beam. If you would be good enough to write up a quick walkthrough of some sort to find all the upgrades.
Well the sounds ripped from Prime are good, except for when Samus gets hit. You should stick to the 2D sounds, they just fit a whole lot better. Trust me, this can only do good.
I'm not saying the screw attack and the charging beam particle effects are not pretty, but it's just too much. Try to tone it down a bit. I don't know how you could do it, but for example, the explosion when a shot comes in contact with a wall, is perfectly well done. There is no uber effect or anything, just the right circular effect. Same goes to the morphball bomb, the particles used are not "too much" nor "too fancy". BTW I'd like to add that the morphball's 3D effect is really awesome!
As for the saving station, AutoCAD is not the way to do it... If you want to sprite, at least try to do it properly : pixel by pixel. I can only recommend that you use one from the original games :
Super Metroid (I see how yours looks a lot like it) or
Metroid Zero MissionBut quite frankly, I would request a custom made one.
See, when you get an upgrade, the game pauses and then the text displays on the middle of the screen saying how to use the new upgrade. Instead of pausing the game until the text has finished displaying, you should allow us to continue playing. Meaning we should be capable of moving while the text displays. Dunno how to clarify it more.
It's not the amount of scannable stuff that you put into the game that counts, it's how the scannable stuff is needed to move on. I'm sure the new environment makes full use of the scanning, and keeps a scan log, right?
Are you going to change the lock-on key and the grapple beam key?
One thing I forgot to say last time, please add information on the F1 screen. It's really better if I want to play offline and would like to remember which key does this or that.
Finally, I'm glad that you posted it on the MP2D fan forums, CoreFusionX is a professional programmer (best programmer I've ever met, blows anyone from ZFGC easily), and the other guys usually give good advice.
I'm eagerly awaiting a new demo with part of the storyline and the new environment, please keep up the good work, it's been a long time since I have been so enthusiastic towards a fangame.