AbleCommerce Shopping Cart Software

First try to find which algorithm they are using to encrypt passswords then do some google search to decrypt password using that algorithm.

You may extend your request time out by going on AbleCommerce Store-->web.Config File -->Finding this section ' <httpRuntime maxRequestLength="4096"/>' and replacing by this
'<httpRuntime executionTimeout="9000" maxRequestLength="4096" />' etc.

You may write a code script in ablecommerce Store. In that script you can connect your database (from where you want to pick inventory details) with ablecommerce store database to update variants inventories.

try width and hieght in %(percentage) instead of pixels.hopefuly it will work fine.

Can you explain what type of functionality you require using facebook Open Graph Feature?

Our FaceBook 'Product Share' module for AbleCommerce has been released.You can check it out here on
http://www.plugables.com/FaceBook-Share-P18.aspx or
http://blog.plugables.com/

Yes this is possible, We made a plug-in that makes use of facebook connect here at plugables which isn't released yet basically needs some testing stuff.