thanks kat, and i found a workaround by rendering just the reflective pass, which blender is doing at the moment, then hopefully i can composite that with the rest of the layers.
and thanks very much for the compliment. this commercial project is still going ahead, be it very slowly from my end, although thankfully the trance musician is very patient, partly due i would imagine, to him have several other psy artists he regularly works with, so i'm not holding him up at all.
as i understand it, the intention is we have different versions of the videos, so in the end he might have the same track on two or three different artist's videos, and likewise i might offer my services to another musician in the future, but for the time being, i'm happy just to be working with him.
when i restarted this project last year, i was reasonably confident i could do this artistically, i just vastly underestimated how much research and development i would need to do with blender, and this included learning the post 2.5 interface. and although i'm working (unpaid) full time on this, my 7 year old, second hand pc is very underpowered, so it takes a long time to render even at the 360p resolutions.
we're intending to publish those for free and charge for the 720p versions, but i won't start rendering them properly until i've got the 360p ones as good as i can get them.
for the first full length video, with music, i've decided to leave out the alien jellyfish, because i still have to improve my animation skills with them, although the models and rigs are built, so i'm practising on the less complicated abstract objects like you see above. i have a couple more models to build and then i think i'll have enough for the first video. and by the 3rd or 4th hopefully the jellyfish will be ready.