Multi-language is a feature that I would need to add eventually, but unfortunately it's not feasible at the moment. You would need to create your own fork of the forum code with all relevant text rewritten in the target language, which obviously is an awful way to go about implementing another language.
There is a flaw in the forum !! (CSRF)
Thanks for pointing this out. I had intended to do this to all the action links back when I added that to the logout function like you noticed, but I forgot to actually do it :V
You can't upload images to Agora (aside from your avatar), to post images in threads you need to upload the image to another site such as imgur and then place the URL to the image file inside [img] [/img] tags.