Thanks to all for the quick response. I'm not yet certain exactly how I want to implement the invitation thing. But that is ok because it is going to take me quite a bit to get comfortable coding for the ACS system.
I don't know tcl and it looks like you have quite the framework one needs to learn as well. But I have found documentation and I'm reading away. For now though I will limit my scope and concentrate on the photo album thing.
Again thanks to both for the help. I will post something once I have it all figured out but like I say it might take quite a while.
//Andy
