Cover objects works like walls in terms of unreachable areas!

[M34T BOY]

I don't know if it's intended or not, but the cover object can be placed on "dead" tiles without displaying the annoying unreachable area icon.
I'll have to see if that poses any problem in the long term, but I'm glad I could fill up some dead tiles without having to place walls that would look weird near the hull (for the sake of ship shapes)

[Flin Fredstone]

Good tip, thanks.

[SiX]

Need option to disable or dismiss annoying icons.

[M34T BOY]

Decoration plants box works too in that regard (the one one the ground)