Just go to the download section of the AAS website. You will need your exiting serial# in order to DL the update.

Strum GS-2 v2.1.0—LATEST

June 4, 2015
Added in this update

• Added the electric guitar model;
• Added 139 electric presets;
• Added 301 electric loops in 43 packs;
• Added Aftertouch Threshold to the MIDI panel;
• Added parameter values entry via computer keyboard;
• Added bank and program navigation via computer keyboard arrows;

Fixed in this update

• Fixed Compare button;

Notes

• This installer can simply be run over your current installation to perform the update.
• This installer is a full installer so you can use it as a starting point if you need to reinstall from scratch in the future.

Awesome update! Thanks for the heads-up.

Thanks for the heads-up 

Did we not get Strum Session with a previous version of Sonar as I cannot find the serial number in my cakewalk account?

JoeOss
Did we not get Strum Session with a previous version of Sonar as I cannot find the serial number in my cakewalk account?

I just check my store account, I still have the record of AAS Strum Acoustic, dated 2012.
 
EDIT : But I think I've actually purchased it at the cake store during a promotion..
 
Contact support ?

Thanks for that, I thought so.

Boy what a great price for the gs1 update.... looks and sounds amazing for a modelled guitar.  
 

I had bought Strum Electric in a no brainer sale way back but did not like it all that much. I was not going to do this upgrade but in a moment of weakness i paid out my $29. I am pleasently suprised! Its a big improvment over the earlier version. It still exhibits a bit of "brittleness" that I associate with physical modeling. It wont be a first goto but I will certainly be using both the acoustic and electric versions along side my Orange Tree, Indiginus and Music Lab guitar libraries.

Brittleness... good characterization.  but it is very nice.  I am quite amazed the modeling has become this good.  I put GS-1 away a long time ago but will update... love the midi for songbuilding

Is anyone using GS-2 then?
 
I updated today because I'm experimenting using Strum "power chords" routed through Guitar Rig. Which work okay, I guess, though not as good as the real thing...
 
For some reason, the Speed, in the Strumming section, doesn't appear to be altering the speed of the strum at all.
 
I might post a query on their forum...