Keyboard Maestro. How to select a file in an "Open file" dialog?

Question

I want to automate search by an image using Google's image search. I was able to automate saving screenshot to a file and opening a page with Google image search. And now I want to select the saved file in the "Choose file" dialog.
How can I automate this?

Answer 1

Eventually I was able to do this by using simulation of the CMD + SHIFT + G keystroke and pasting a path to the screenshot. Here is my final macro