For my "Les Paul" type recordings I used to use Tempo ratio to slow down a midi track by exactly half ....there were three Tempo thumbnail Windows titled 1-2-3 ...2 being normal....

Well that's gone in my upgrade and my old Sonar versions display incaptatible when using midi out so I'm not able to use it.

So....is there any way to reduce a midi tracks speed by half which would also include various tempo fluctuations ?

See this post for a workaround to scale tempos. But in your case, you'll have to do it again the other direction to get back to where you started:
 
     http://forum.cakewalk.com/FindPost/3267464

In the tempo view you can set any tempo you want, you can also draw in tempo changes to emulate tempo drift. I use this technique a lot for my drum tracks, it gives them I little more life and sounds more natural IMO.

I think Process > Fit to Time might do what you want:
https://www.cakewalk.com/Documentation?product=SONAR&language=3&help=Dialogs1.63.html
Here's an old thread:
http://forum.cakewalk.com/Need-to-Change-overall-tempo-with-many-variations-already-in-place-m1912817.aspx
 
 

Oh yes...I remember I've seen this process /tip before ....I think I tried it once and it worked but the Tempo Ratio was a simple option however, now that's gone I will be using this method

Many thanks ....