Yes, but don't use the Armor in Space. I don't think the Mod Author made them Vacuum proof yet.

Sort of... there appears to be issues growing clones and sleeves right now, also no vac on armors is a thing.

Patch fixed the issues it is working with 1.6! No vac suits yet but the mod is working!

No, it doesn't work with 1.6. Once you set up and use a SleeveCasket, you can no longer launch the GravShip. You can initiate the launch, and the ship will take off from the map. But as soon as it switches to the world map, the GravShip is stuck. And there are a lot of error messages that mention something about SleeveCasket.

i have sleevecaskets but my gravship works fine. haven't tried flying with a sleeve in one though.
but empty sleevecaskets gave me no errors

Forget my comment, Harmony messed everything up. The cards have been reshuffled for all modders.