I managed to display the Save As... dialog automatically for new maps by editing DITA\MAPMANAGER\js\DitaMapHandler.js:
DITAMapHandler.prototype.initFromString = function (filePath, mapAsString, resourceLocator) {
// ...body of function is unchanged
this.SaveMap();
}Not ideal, but it works. If anyone has any advice on a cleaner way to implement this, especially if it can be put in a customization macro, it would be much appreciated.
Thanks!