I was really excited to see the label specifying mekanism gas is supported in your fluid input and outputs. The problem is, there is no way to get the gasses into or out of them. Your block does not register as a container compatible with the Mekanism pressurized pipes. See picture. I also tried the Galacticraft gas pipes, but they did not work with the gas tanks.

That indeed is weird. Will double check that in a sec.

Reproduceable and probably know why. Will fix that for the next release.