Yes, using the [ img ]
http://www.yourhostsite.com [ /img ] code you can have up to FIVE (5) linked images from another site in your message...
Example:
[ img ]
http://www.yourhostsite.com/image1.jpg [ /img ]
[ img ]
http://www.yourhostsite.com/image2.jpg [ /img ]
[ img ]
http://www.yourhostsite.com/image3.jpg [ /img ]
etc...just remove the spaces in the [_img_] code(s), this is only for examples...
You can post photos (bigger) in the photogallery and then just linked them up into you message.
Yes, uploading is limited to 75K, a good file size is 640x480 and less then 75K.