Item #1: during my search I found this video (for sure you've seen it):
first I thought this is a joke and the guy is drunk or something else. then I tried his solution - ALL cables (PS3 component, TV hdmi) on the output side - and it curiously worked...
Item #2: works fine without USB connection. I have only component cables used and no more hdmi cable is necessary, the quality is still the same.
Item #4: I wasn't able to receive any preview on my PC. at the display settings (PS3) I had the following options: 576p, 720p, 1020i, 1020p. selecting 576p was the only way to get any preview. trying to capture a video was impossible - video was only 1 second. then I realized that it could be the LG L222WS monitor which was connected to my Acer notebook - it's connected via VGA RGB cable (yes now it's clear - no HD). the monitor is used extended so that I can work with 2 screens. after disconnecting the monitor I had a preview with 480, 720 and 1080 on my PC and capturing suddenly worked.
I hope this sounds better.