Sounds like an interesting project. I can make this with Python. I work on a Linux system but I can switch back to my Windows system for this project.
The way I see it, the GUI will have only a couple of things. Search words, filters, and a submit button that will run the crawler. It will open a Selenium Web Driver and start downloading each photo in the results and scroll down until the specified max downloads variable.
Message me so we can discuss in detail.