If you want the image to be the thumbnail size, then you would go to your gallery, and not select/open up the image in your browser. Instead, you would right click on the thumbnail size that gives you the previews
I chose the "copy image location" and then paste that (the mountaing image]
If you want to get fancy, you can select your gallery page, right click and chose "copy image link", come back to the thread post, select your thumbnail/image, click the icon with the world, and paste in the url link.
This will the make the image clickable.
To make words clickable, you do the same thing
type in something like my challenge layout, highlight the words, and then click the world, and paste the url
you can paste images in thread/forum posts, but not in gallery posts
hope this helps