Yes they came with a Velcro strap for under the seat and yes it is on and tight.
the front and rears did come with some brackets but not a support bar. I have never had uncut fronts and ive never ran a suport on any of my rear plastics before and these new ones seem to be pretty stiff and shouldnt flop around.
As for the hood in that first picture the bolts are not tightend down so yes it does pull the sides in a little for a better fit, but the hood is still a tad longer then the sides. I'm going to try and mess with the brackets this weekend and see if I can't get everything to line up better.
And no the plastics are not hitting the tank.... I will try to take some better pics to post up do you guys can see a little better. But as of now you can see the ground by looking between my plastics and the tank, it's off by quiet a bit and it will really bother me if I can't find a fix for it!!!