In answer to your questions:
1) Outside of making the customization yourself, you may wish to look at the
Image slider plugin for Vantage available in the AppThemes marketplace for another image option.
2) There are no default options in the theme to allow charging for specific number of images, so again this would require customization on your part if you were looking to implement this.
3) There are no options for tracking this specifically.
Our themes are not encrypted, so you are free to make modifications if you wish. You can also find developers for hire in the
Certified partners page who are experienced at working with our themes. Thanks.