Paper 2D tile map and tile set

Hello

I was trying to use the tile map in paper 2D, I know is an early access features, but I would like to know if is just me or is not implemented yet.

First I was trying to use Pixel per Unit in tile map but it looks like nothing happen do I have to do something specific to use that option because for now selecting an image and a setting a number it seems not work.

Then I was curious about collisions once I import my map in the game do i have to set all collision manually ? or is there some particular place where I can do it easily ?

thanks for the help