My experience is similar to that of adp001. Ie. Poser 7 installs and runs fine in Ubuntu (several versions up and including 8.10. and with most current stable Wine releases). But the SRs had to be installed via a virtual Windows (I use VirtualBox; not the OSE variant but the restricted one that allows USB-traffic from Ubuntu to a virtual machine).  Using a virtual machine just for installations is relatively easy and straightforward. Been running P7 exclusively in Ubuntu for almost a year now and I'm quite happy with the performance.

JenX, you can try running the Poser 7 installer with wine from a command line in a terminal window. Wine gives out huge amounts of technical details for any problems it encounters. Maybe you can catch something that help you out by watching the output Wine generates. You can't see this output if you just click the installer exe in Gnome.