Help I am About to Put in New Flooring

[AustinAir]

I removed the carpet from my 1973 31ft Rear Bath sovereign and found a small rotten spot by the door (1" x 5") I was going to fill that with bondo auto body filler and sand. Will that work?
My big concern before I put down the flooring is that the plywood seam between the kitchen area and the bedroom does not meet cleanly. The bedroom piece seems to be free floating at the seam. Is it supposed to be this way and if not how do I fix. Can I put a threshold there and install flooring?
Thanks for any help

[cameront120]

A threshold would make the most sense if there is a seam that has any movement. That seam will transfer to the flooring and will be quite visible (assuming you're using a vinyl flooring of some description). As for the small rotten bit, once the leak is repaired, you could cut that bit of rotten plywood out and scab in a new piece. Fill any seams with a non-shrink wood filler.

[AustinAir]

My flooring guy way able to secure the piece of plywood with some wood screws and we chiseled out the bad wood and bono in the spot. The leak had already been fixed.
Thanks for everyone's help.

[vinstream]

FYI....Please do not use Bondo... It is great for filling the problem but I would try to find something that has more strength... Fiberglass or floor leveling compound with layers of mesh would be the way I would go... GOOD LUCK!!!