I have Poser4 and Poser 5 I do use both. I find I will create in Poser4 and then will do finishing touches in Poser5. I have narrowed down my problems to the amount of lights used. I got the Environment Creator for Poser5 and so far I am very happy with it. I still have the light issue if I want to use DOF; but the control over the lighting is wonderful plus you can delete all the lights with a click of a button. Over all I am happy with my purchase(the upgrade price made all the difference to me)and I have had alot less problems than I had with WinXP. I run win 2kpro, 768 ram AMD 1733+ chip and an ASUS 7v333 motherboard and a geforce 4 mx440 videocard. Marge