OK, sorry if I misunderstood you.
So, you installed Lr on two different computers, and on neither of them you can see the presets - Correct?
Did you install from a CD?
If yes, I would suggest this: download the trial version of Lr 4.3 from Adobe's website, and install it. This is the link: https://www.adobe.com/cfusion/tdrc/index.cfm?product=photoshop_lightro om&promoid&promoid=DTEML You have to select your OS in the small window.
The trial version is the same as the unlimited version with all features enabled, except it runs only for 30 days.
When you install you will be asked, if you want to buy or if you want to try. Select <Buy> and when asked enter the serial # from the back of your CD. This will change the trial version into an unlimited version.