when should you be parrying to ripsote? I'm not quite clear on the timing
do you want to hit R2 when it makes contact, or slightly before? the parry animation is fooling me
Slightly before. I almost never use parry though since it's risky. I just block, wait for the enemies to get staggered, and then counter attack. Or you can roll, either way.
About the mid-boss on the bridge
spoiler (click to show/hide)
you were supposed to climb the tower and then jump off and hit him with the downard slash. Kills him in 3 hits.
You do get shortcuts to the bosses, just like Demon's Souls. Sometimes they'll just place a bonfire a minute away from the boss, so running back to retry isn't too annoying. You also get shortcuts (elevators) that lead back to the main hub area (Firelink Shrine), but sometimes it can take a while to get back to them. Just make sure you remember where they are, because this game doesn't have a map.
As for the Master Key, you can actually use it as many times as you want, but it only opens "basic" doors. Meaning, you won't be able to unlock shortcuts or new areas or anything with it, just some random houses that might have some loot and a tough enemy. And any character can pick the Master Key as their free gift as well, so that review was wrong (again).
The blacksmith is a little further ahead, just before the first boss. He can repair your stuff (repairs are cheap too, only a couple hundred souls at most). But make sure you buy the repairbox from him, and his two other toolboxes if you can. They're 2000 souls each, but they let you do blacksmithy stuff at campfires instead of traveling back to him.
It's just Blighttown that's been really bad so far. I'd guess that all of the light sources are what's causing it to choke, since the stage is pitch black with lots of torches all over the place.
Did you install? Just got home and chucked in the game, it's already amazing. The male Eerie Great Swamp face
going with Jubilant Catarina
Yep, though I doubt it really does anything since the game world is entirely streamed. It only loads when you die, and the loading is quick. That's one nice improvement over Demon's.