The pitch is customizable in Scala (.scl files) tables.
In other words, much like tuning a piano, you have to set it up to the temperament you want first, (you can also change the tuning from A = 440Hz to Baroque, e.g. A = 415Hz.)
But included with the CFX are many tables like Rameau, quarter, fifth and sixth comma meantones, temperament ordinaire II, Kirnberger & Werckmeister III, etc.
But it's not the pitch of your own keyboard you're changeing, it's the pitch within the Garritan player, built for them by Plogue.
The application has many controls to adjust for full and half pedalling etc., etc. so it's as well to read up extensively on how it works to see if it's suitable.
A simpler solution might be to opt for GPO5 which has both pianos and a harpsichord as well as a whole host of other instruments in it.
The piano isn't as sophisticated as the CFX but is still quite good.
Garritan Personal Orchestra 5.
I think the sampled piano is a Steinway? You won't need to do as much 'tweaking' as I have done, and you get loads of pretty good sounds for a low cost.
But, if you haven't messed around with VSTs before, be prepared for a rather steep learning curve.
Quite a bit of reading is needed to understand how it all works.
There are online manuals and downloadable pdfs at the site above.
(
With my old Thinkpad T430 I upgraded the CPU to a quad core i7, the little cover comes off the bottom of the casing and a micro 256GB SSD can be installed there to carry the operating system, (the BIOS needs adjusting to boot from this) then the hard disk was replaced for a high capacity 1 TB one. Lastly the CD drive is removable and a holder for a HDD installed in its place. Into this I put a 500GB SSD for the samples.)
JohnG