The Genesis Generation X plugin will currently not work with DAZ Studio 4.5 because all plugins need to be updated for the new DS version.
The DSF Toolbox should still work with DAZ Studio 4.5, but only for uncompressed DSF files.
I will release free updates for both applications as soon as possible. I will announce their availability here in this thread as well as on my web site (d3d.sesseler.de).
It’s the first time I do updates for products at the DAZ store, but as for as I know, the updates will be available by downloading the product again from your DAZ account and you should get an e-mail notification when they have been released.