If it's ok with you Casper I have another way of adding images.
Since Flickr has been updated you can now copy the BB code.
Here's what I do.
1.Click on Share above the photo
2.Click on Grab The HTML/BB Code
3.Make sure BB Code is ticked
5.Make sure the size selected is within the forum limit
6.Right click on the code and copy
7.On your forum post right click and paste or hold down CTRL + V
It might sound a bit long but Flickr remembers your options so you will only need steps 6 & 7 so it's just a quick copy and paste
Paul