I know, I might be a little annoying posting up these little files of mine, but after having a breakthrough (and a minor breakdown), I came up with a portal solution that is just so simple, so elegant, it is "Insanely good" ...
Honestly, I have not tested this for Time and Timestamp, but the principal should work, as it works for date, text and numbers.
I might sound like I'm beating my own chest here, but honestly, this is a very neat solution and it would be quicker than most solutions I've seen.
You're going to kick yourself when you discover the secret to the portal sort and you're going to laugh when you see how I've achieved the ascending/descending component, I took the approach "if you can't make it, fake it".
Please take a look. the solution could work well and can be retro-fitted to existing solutions. It requires a little more layout trickery, but the result is super !