The order doesn't matter as long as you don't install eCart last. You just can't install eCart over top of the consolidated extensions without reinstalling one of them.
Your friends over here at WebAssist! These Dreamweaver extensions will assist you in building unlimited, custom websites.
These out-of-the-box solutions provide you proven, tested applications that can be up and running now. Build a store, a gallery, or a web-based email solution.