if somebody needs C# example then:
var registry = Registry.ClassesRoot;
var subKeyNames = registry.GetSubKeyNames();
var regex = new Regex(@"^VisualStudio\.edmx\.(\d+)\.(\d+)$");
foreach (var subKeyName in subKeyNames)
{
var match = regex.Match(subKeyName);
if (match.Success)
Console.WriteLine("V" + match.Groups[1].Value + "." + match.Groups[2].Value);
}