Here is the result of 2 castings each (not completely though, some bits went wrong) of all cave moulds. I used some fieldstone floortiles to put them on, I might give those a whiter brush later to make them look more fitting. Some parts are glued wrongly in the first batch, so I'll need to have another go to complete some of the double pieces, like the wooden door. Still, the images clearly illustrate the feel of the blocks, they look great and will work very well for RuneQuest and Call of Cthulhu, as well as any other skirmish type game, 28 mm or not.
The rocky caves, mould 81 & 82
The water caves, mould 83 & 84
Entering the water caves. Using fieldstone floortiles