No start...timing good...leak test bad...need help

[rah rah 986]

Late fall is the last time I drove my '98 boxster. Prior to that day I had owned the car for three years. I purchased it with 56k and put 30k on it. The engine has run good from day one with the exception of cold start rattle.

One fine fall day, I got in to start the car and turned the key. The car immediately fired once, but failed to turn over. Typically, the car has always fired right up. But, on a few rare occasions, it had required turning the key a second time after an instance like this one.

I turned the key again to start the car and let the car crank for a couple of seconds. I stopped immediately when i noticed it sounded as though the car was cranking with low or no compression.

Fearing a timing issue that might be worsened by further attempts to start, I left the car parked for the winter and have now started the process of trying to figure out what is wrong. I have viewed this as a learning opportunity, and an opportunity to address some larger maintainance issues along the way while hopefully fixing whatever is wrong.

So far I have pulled the engine, drained oil, checked the timing and done a leak down test. The timing marks all line up perfectly, the oil and filter are clean, and the spark plugs look great. No oil on the plugs..totally normal in appearance.

My leak down test is not near as positive. Every cylinder is leaking between 75%-90%.
When listening for where the air is escaping, it is leaking through the exhaust on every cylinder except #1, which I can hear air through the throttle body.

Can anyone provide me with some direction on what I might be up against? I am ready to tear into this thing, but, am hoping to get a clue on just how big a learning experience this might be.
Thanks, Rick