I was hoping to see the pics.
When you do a post fill in the post body describing then click on manage attachments.
That will bring up another window with a browse to click on. That will take you to your PC and then you bring up your pictures or picture of your gun that you want to post. Double click the pic in your PC file. It will come up in space next to browse where you were. Then click on upload next to browse.
Don't close the window and click on preview post. If the pic came through then click submit.
You can close the browse window after it has posted.
Try that and see what you can do with it. I am far from MR PC myself but I was able to figure it out.