Automate Install of Firefox Then iMacros AddOn.

I believe my process is pretty simple & straight forward. I want to pckg the install process into an exe file or single click install for my tiny iMacros webcrawler which is a browser add-on. It needs Firefox Version 21 or up. The coder guy who made the bot gave me an xpi file that installs the iMacros add-on, and he gave a js javascript file that only needs to be copied into the iMacros sub-folder after iMacros installed, and an html file that must have a folder created to insert the Html file which must be opened/used only in Firefox. So the auto-install will need to install Firefox browser if it is not present, or update to current if version is not 21 or higher, and for better user experience we need browser settings to be set in its options/settings to 1) Open/Run Firefox upon install completion. 2) Set browser to Always ask Me Where to Save Files” in the General Tab. 3) Uncheck the Use Hardware Accelleration box. 4) Set browser to Do Not Make Firefox Default and Don't check or ask again. 5) Place the loaded Html file location onto Bookmarks Toolbar to easily locate & Launch. 6) Launch/Open the Html file. The reason the bot coder has XPI file that performs the install & activation of the iMacros browser Add-on, is because he has certain settings established that would not be set if the add-on were activated thru the browser's plug-in selection process tabs. The attached zip file simply contains the iMacros XPI file and 280k Firefox install controller which downloads/installs the full browser files. The js file and html file will be sent to the selected Freelancer. One other thought is that Firefox will likely roll-out newer versions of this small install handler (current file has 35.0.1 in the file) therefore, I would like this install packager to check for and download/use later version IF one exists and/or IF one can be found and downloaded, and reason for wording this way is that Firefox may change the location that we originally use to verify version and institute download, so I want there to be at least a previos version of the Firefox install handler to give us best chance for the user to get a browser install anyway, since it is likely that Firefox will keep supporting previous versions of that install handler for a long time. Here are the instructions from the crawler's coder. Instructions: 1. Download and install Firefox [login to view URL] 2. Unzip the file i sent you 3. Open the XPI file with Firefox and install the plugin; then close Firefox 4. Place the JS file in the "Documents/iMacros/Macros" folder 5. Open the HTML file in Firefox.