Can't change map pathing

[AlicanC]

I am modifying an existing map, but I have a problem. When I turn "View -> Pathing - Ground" on I see grey places that I can't put any units in WE and can't pass in W3:

How can I modify that gray place to free up some space for my modification?

 

[1-Cent]

Screnario > Map Size and Camera Bounds... > Then you find it there

 

[AlicanC]

I am trying to modify here (In yellow):

Edit:
Here is another screenshot:

 

[1-Cent]

Try to use the "Remove Boundary" beside the Textures, under "Terrain".

 

[AlicanC]

Try to use the "Remove Boundary" beside the Textures, under "Terrain".

Thanks!

 

[1-Cent]

No problem ^^