Photoworks:where's my glass gone?

aaaarrrrrggggghhhhh

SW2006 SP1
2GB RAM
P2 3.6Ghzy
ATI Fire 5600

Photoworks: Indirect Illumination (minimum as I dont have all year)
Memory management ticked, highest anti alias, no lights - just indirect
lighting

I have a scene with a bottle in it, using 'white glass' but changed to a
green colour. I render in preview and it's fine (great in fact) and then I
send it to render to file quite big and it's fine, then I send it to render
at 4000pixels across and it takes four hours and I come back and MY GLASSS
HAS BECOME A SILOUHETTE OF SMALL GREY SQUARES.

How do I explaing this to the client who wants the visual?????

Can anyone help me get my glas back, even if it means re-rendering?

Thanks

 

ok, sussed it - bit stupis of me really. I saveed it as a ping and so there
is a transparency map thing going on, so when viewed in Photoshop you cant
see hte colour! Save as JPG from photoshop and suddenly there it is!

Phew.