The high memory usage was due to each organelle loading its texture (instead of there being one copy). There is now a partially working solution (I think it causes everything to be loaded exactly twice):
Fixing this properly needs a bunch of changes to the resource import process to create a manifest file. The good news is though that there was no memory leak related to bsf. However I did find one small(ish) memory leak, that is now fixed in Leviathan.
I’m also working on moving my custom hacky bsf setup, to be supported in bsf directly: https://github.com/GameFoundry/bsf/pull/391