Report of the GAP issue....

I posted about the issue of the gap between the rear bumper and the body panel few threads before.

I brought mine to a Toyota technician who is my best friend today. And he answered like below...

1) the gap between the tail lights/head lamps and the body panel => Toyota FR-S had a issue with waterlogging in the lights because of poor sealers. So Toyota changed all tail lights & head lamps with much more sealer for their all models. After that this issue started being reported. But there is no solution for this.
Even if you don't have this issue NOW, if you get your lights replaced later on, you WOULD have this issue.

2) the gap between the rear bumper and the body panel => Toyota HQ is already aware of this. It is caused by it's unconventional material(for good MPG). Especially during summer, it could be worse, if you park in the sun light.
HOWEVER, it depends on luck on your side... it means mine was out of luck.