Bill, I used to block up my cutter before I got a tractor with an FEL, but now I always lift it up and lean it against a tree. Like you, I've never had any leakage. I believe the filler/vent was on top when I tilted the cutter up, so it was never in fluid.
I've never had my blades stick like yours. I think the combination of how long it sits between uses and the amount of humidity trapped under the deck might contribute to the sticking blades. I've sure started the cutter turning a few times with the blades partially stuck and had the cutter do a "dance" until it got up to speed, and centrifugal force put the blades into the correct position. /forums/images/graemlins/smile.gif