Well i noticed in the page w/ encounter slots that it also has the slots for radar (which should take up slots 6, 7, 10, and 11 according to the site w/ platinum encounter slots). I'll probably bring a static pokemon with me to help having a likelier chance.
And just saying about the second question, I just want to use it so that the chain "should" start in that first battle. I guess I'll just try and see what happens. I'll try the turn and step, but the problem is that I'm having to go for frame 109 (highest that the spread appears on), so that might advance it too much.