How to use the read/writeable local XML settings?

Question

I found something similar to what I need here: http://www.codeproject.com/KB/cs/PropertiesSettings.aspx But it does not quite do it for me. The user settings are stored in some far away location such as C:\documents and settings\[username]\local settings\application data\[your application], but I do not have access to these folders and I cannot copy the settings file from one computer to another, or to delete the file altogether. Also, it would be super-convenient to have the settings xml file right next to the app, and to copy/ship both. This is used for demo-ware (which is a legitimate type of coding task) and will be used by non-technical people in the field. I need to make this quickly, so I need to reuse some existing library and not write my own. I need to make it easy to use and be portable. The last thing I want is to get a call at midnight that says that settings do not persist when edited through the settings dialog that I will have built.

So, user settings are stored god knows where, and application settings are read-only (no go). Is there anything else that I can do? I think app.config file has multiple purposes and I think I once saw it being used the way I want, I just cannot find the link.

Let me know if something is not clear.