I was quite desperate after making like a little 'trawler' to help me move a base unit. The base's docking port didn't have the dock option, but the rover's did. However upon clicking 'undock' not much happened, and sometimes it seemed to invoke the Kraken.
I found this guide for editing the persistence file on reddit, but it seemed my persistence file was ok.
In the end, what I did was change the 'DOCKVESSEL' node's 'rootUid' value from what it was originally (a cubic strut on the rover, as I had moved the root part to fit it on the rocket) to the rover body's rootUid and this fixed it. Just wanted to post this in case this might help anyone else!
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