Prior to this fix follow install instructions.

Fixed – Commenting System
—When adding comment, page would not refresh
Fixed Deleting transaction records
—Now you can delete transaction records
Fixed Logo Upload
—When uploading logo an error would suggest that file is not jpg, png or gif
Fixed Gateways
— PHP Notice: Undefined index
Fixed Maintenance mode
—Missing maintenance page

Version 2.0 was completely rewritten from scratch
New Menu Manager – allows you to place you content menus anywhere on the page
Categories – Now included as part of main navigation
News Announcements – Easily announce important information to your front end clients
F.A.Q. – Built in FAQ manager
Newsletter – built in newsletter manager
Coupon/Discount Manager – Easily create 2 types of coupons percentage/number value
Payment Gateways added MoneyBookers and AlertPay besides PayPal
Delete inactive users
Delete banned users
Two types of file manager Simple/Advanced for easy upload of large files.
Products – added audio preview, youtube link and product tags
Full Ajax interface front/backend
5 additional front end plugins: Bestsellers, Most Popular, Related Tags, Recently Viewed Items and simple advertising plugin
Notification when comment is posted on/off
Notification when user is registered on/off
Notification on every purchase successful/unsuccessful
Better SEO for products and Categories
Plus many more

From previous version – but all rewritten:

Commenting system
Product Gallery
Ajax Search
Full page search
Built in contact page
Voting/Rating
Rss for categories