Hi Paul,
You may want to set up your profile so that members here can easily email you securely through the club server. There is a setting that adds a link under your avatar which will look like a little envelope. Below are the specs needed to post pictures...
First reduce the physical size; the maximum height is 1,200 pixels and the maximum width is also 1200 pixels. Next is reducing the file size; the maximum file size if 500kB, and no more than 10 attachments per post.
Once you have the right sized images preview the text of your post which will bring up more formatting options if you started in Quick reply mode. There will be a little plus mark below the message box next to the text "Attachments and other options". Click on that to attach photos, unfortunately they don't seem to preview so you won't see them until you post the message. Good luck!