We now have a short illustrated guide to inserting images in forum posts. You’ll find it in the Resources section of Downloads (under 4 Miscellaneous). [This document has now been deleted as it has been superceded – see blue text below].
[Update 18/10/12: We have a technical issue that’s preventing members from inserting images in posts. This is being investigated.]
[Update 19/10/12: It seems that our web designer has now modified the Forum. When you are writing a post and want to insert an image you switch to the HTML screen and tap the little button marked ‘img’ (it’s above the editor window) then fill in the form you get. You must have the image URL ready for this.]