You should be able to just click on the icon (which says “add picture” when you hover over it). A screen will come up that gives you three options. If the photo is in a file on your device, you should click “browse” and find the file. Then either double click on the photo file you want or click “open” and the photo should come up. Then you can click on the green button on the lower left that says “Upload 1 photo.”
If you aren’t getting a pop-up when you initially click on the icon to “add picture,” it could be that your settings are not allowing for the pop-up or you might need to try a different browser. I can get this one to work with Google Chrome. (I have other web pages that will only load completely in Explorer.)
I hope you can get things worked out. You can always contact Martin at email@example.com and see if he can help you figure out what is wrong. It all seems to be working okay on my computer.
“Those who would give up essential Liberty, to purchase a little temporary Safety, deserve neither Liberty nor Safety.” Benjamin Franklin