Just upload it to imgur.com then copy the Direct Link URL (the one with a JPG or PNG file extension), click the image icon above the post reply box, and paste that URL in there. It should show up.
I'm not sure what you have in the way of pirates, but I would try the following. Send in 2 or more Brutes to distract the Mortars and gun towers (either from the top or bottom) Follow them in quickly with a few gunners to shoot out the Mortar, gun towers and bunker Then Bombers to crack the wall while that is happening Once you have an opening add a couple of Jugs and the rest of your gunners If you have a Witch doctor drop this behind the rest of your troops for protection Get back to us either way. Good luck..