Justin, as with your skin problem, I am unable to duplicate this with the DNN 5.0.1 installation on my test system. Is it possilble that the DNN skin you are using does not allow for the panes to expand with the content? The product data entry module is pretty wide and if you have a fixed width set in the pane where it resides, that might cause a problem I would think.
Are you working with a fresh install of DNN and Catalook or have both been upgraded from earlier versions?
Ed
DNN 5.0.0 was not ready for prime time. I'm hoping this new release will work a little better. Hopefully that will fix your problems.
On the test site I'm using to evaluate the latest DNN as well as Catalook, I use a skin called Flex by DrNuke.