OK, I see where you are coming from. Some people telling you that Progress is only good in combination with a database and now you have the challenge to prove that it can do other things as well by making a solitaire game...
I am sure it can be done, but it will take you a bit of effort. Drag and drop of widgets = your cards (assuming you will want to make it similar to the MS game that comes with Windows) is not very well supported by Progress. It is for instance very hard to see where a widget is dropped. The selectable and movable attributes in combination with the end-move trigger are supported but afaik other than working with x and y coordinates there is no way to see on top of which other widget something has been dropped (and you will need something like that to make this work).