As the gallery name suggest, it is underground in a crypt, a fitting location, given the subject matter.
After recent flooding, it's rather slippery underfoot, so you'll want your caving boots on if you visit!
I can't profess to be any kind of expert in this field. At my level of appreciation, some of the works caught my imagination, others I did not "get", but the thing that really struck me is how powerful (and different) the emotions are that caves seem to inspire in people.
If I could pick a main theme that continued through many of the installations, it was the sense of disorder that the artists seemed to find in the underground world. A secondary theme expressed through several works was that of fear and isolation.
These seem to be the emotions that caves commonly produce in the "non-caver" and perhaps can be tied back into the thread about "questions from the general public" https://ukcaving.com/board/index.php?topic=24682.0
I think these emotions change as our experience of caves changes. Where we saw disorder, now we see patterns; patterns of rock formation and patterns of erosion, that combine into the disorderly order of a cave. Where once there was a fear of the unknown, now we are drawn to the unknown, most at home when we are most isolated from the world.
It would be fascinating to see how these artists work might change if they took up caving or digging and and revisited their installations in years to come, with a new perspective on the underground.