Quote SpaceHopper (

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A parameter such as: 'NoCollision true' might help. Then we could fly through an object as the gate.
Now that you mention it, it might also help with your Star Cage and Hollow World addons.
No.
It is possible to enter into these objects when in the 'user.cfg' for 'Clip Height' a negative value is set.
But then everything is invisible. SpaceEngine does not render an object if the viewer is inside of this object.