Ok, thanks for all of your suggestions. I have released a new version of the plugin (same download link as above).
News:
[*:3466sfj6] There is now a button called "Original" which you can hold to show the source image. [*:3466sfj6] The menu item appears in the correct menu also for non-english versions of PDN [*:3466sfj6] The filter size default was changed to 30 for a more distinct result
I tried this, but the GUI did not behave as nice as I can make it with my own dialog. Have a look at my comment to this topic in the development forum.
Yes, I am. The Increase Local Contrast effect also exists in IA but with a few more options. I have considered making more of the features from IA available as plugins for PDN.