Not doing so Hot - Burning leafs, White powder buildup

[Ninjaneer]

I think your right about the edema, google it and you see very similar symptoms.
 
Those pictures look Exactly like what I had at the beginning of this thread; Those are the first images I've seen that really looks identical thanks for posting.
 
You can try all the things I did.  I think the complete flushing then letting the soil dry out and breaking off the dead leafs (to help redirect energy to healthier parts of the plant) is what really did it.
 
I transplanted it Last Friday into a new bucket with "potting soil; there's a huge difference in the soil consistency.  The bucket full of "gardening soil" I had it in is STILL wet today from like 3 weeks ago when I flushed it out!
 
Maybe you could put a fan (or anything to move dry air past the soil) on the plant to help retard the growth

 

[OhioHeat]

In the past I have used a a mint leave/water solution to aleviate the "white powder" fugus. Do a web search for the proper instructions. It worked great for me and it's a natural remedy.
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I vaguely recall using about 20+ leaves crushing them and adding 1 cup or so of hot water , let it seep and from there I strained and put in a spray bottle. Spraying both the top and underside areas and within a week my white fugus was gone. (also mint is a good natural repellant for some bugs/critters)
 
...another resource idea. ....http://www.ehow.com/how_4819729_rid-mold-zucchini-squash-leaves.html