Seems the buildings from this mod are no longer placeable on spaceships, as of Space Exploration Post Process 0.5.21. The blacklisting was done by looking for "Factory" in the name of any structure declared as a fluid storage structure. No point in trying to work around it mod side, since that may get the mod blacklisted altogether. It it was intended that this is usable on space ships, this is now no longer the case.
The general problem is that a spaceship with a factory building can bypass quite a few limitations, one of them being having a large number of storage containers. Another, is in the case of Krastorio 2, there are some power generation options that are quite nice. Placement of a singularity reactor directly on a space ship intentionally nerfs its speed, to make it rather difficult to use singularity reactors on victory space ships. Also, an Intergalactic Tranceiver is not able to be placed on a space ship either. That was intentional, since an activated one provides a permanent 10GW power source. Both limitations bypassed by being able to have factory buildings on a spaceship. (Although you do have place enough power generation inside of the factory building along side the intergalactic tranceiver, since it will NOT charge off of outside power.)
(Mining an activated intergalactic tranceiver causes it to lose all power, but being able to place one inside a factory building and charging it up there means you never have to move it, and can in fact declare the factory building as a power source rather than a power sink.)
Finally, likewise, this bypasses the hull stress limits too, since you have effectively unlimited building space thanks to factory recursion.
