Insert a label somewhere. For example, you might want to have the dialog sensitive to the active document, so you could have a document label that you seek out and set:
If (app.documents[0].extractLabel("Selected Country") == "") {
// document doesn't contain a previous selected country
} else {
// it does so use it
}
Then, on receiving an OK from the user after the dialog, you can set the new value:
app.documents[0].insertLabel("Selected Country", myLandList[myLandMenu.selectedIndex]);
If you use the actual name of the country rather than its index in the list, it would allow for adding new countries at some point in the future, but if you do that, you'll need iterate through the list to get the index on the way in.
If you just want a single value across all documents, do the same thing but insert the label in the application object.
Dave