You can adjust the height scale of the image under the General settings:
Within the next month or so, we will be releasing some new features to enable more user control over z-height scaling.
We are also considering implementing your suggestion to add the ability download the image as a .tiff file. In the meantime, you can always take a screenshot of your web browser.
We are making frequent updates to our site - as often as every week. You can keep track of new features/updates to ProfilmOnline via the Website Change Log.