Lol man dont worry! Shit happens xD. I once did a project for an important client and I saved it to 70dpi quality instead of 300 lol. It looked like hell and I had to start over xD. About xml its much more dynamic way to import things in flash. For example your gallery. You have the .swf published file, a folder with the images and the .xml file (similar to text files). In the your project file you code some lines in action script to import the links from the .xml file. The .xml file structure is simple. For example :
Code:
<xml>
<gallery>
<image></image>
<image></image>
</gallery>
</xml>
You can also tell flash to set proprieties like the speed the animation slides in the animation pattern that is used etc. I'll try and find some good tutorials for you.