[Blurayx]

The aspect ratio is correct, but because of the varying types of artwork the dimensions of the space allocated to the artwork doesn't always suit the specific artwork type.

Horizon allocates a square space regardless of the type of artwork, hence the gray frame around the 12 monkeys poster. Doing this in Grid will result in things like

which to me is worse than one window having this problem.

In the favourites window it is impossible to adapt the dimensions of the artwork based on what type of artwork is being shown (aside from treating everything the same resulting in the above), as Kodi does not provide the skin with information about the content type, like it does in other windows. This is also why in the favourites window you are not seeing metadata like you see in other windows.

Ok, I understand now. Amazing skin but limited because of Kodi.