For the size of your pictures, it depends on whether or not you upload them to Fauna or if you remote-link them. This means that you actually upload the pictures to your website and use HTML to input them into your post. Example:
<img src="http://www.geckophiles.com/images/breeders/02.jpg">
For that I used this tag (without the period:
<.img src="http://www.geckophiles.com/images/breeders/02.jpg">
http://www.geckophiles.com/images/breeders/02.jpg is the link to the picture on my website.
So if you upload a picture to your website, then you can use the same tag.