Installer framework version in config.xml and package.xml

[michjans]

Hi,
I'm trying make an installer for my application (containing only one package). There are two places in the installer where I have to enter a version number. One in config.xml and another one in package.xml. In my case there is no difference, because there is only one version, but both fields are mandatory.

What is the difference of both fields in case of just one component?

Also, I would like to show the version number on the introduction page, but the variable @ProductVersion@ is not replaced in the install script, e.g. this does not work:

Controller.prototype.IntroductionPageCallback = function()
{
    var widget = gui.currentPageWidget();
    if (widget != null) {
        widget.title = "Setup"; 
        widget.MessageLabel.setText("This tool will install version @ProductVersion@ on your computer."); 
    }
}

Is there a way to show the version number in the welcome text using a variable?

Thanks in advance!