I am using Photoshop CS4 in Windows 7, and it’s very easy to apply the Photoshop CS4 styles in this version. All you have to do is load the styles directly from inside the program itself.
I used to use Photoshop Elements, and in the earlier PSE versions, I had to make metadata files of each of the styles and then copy-paste them into the Adobe folders. Then, Photoshop will load them (which will take some minutes or longer) into the system before you are able to apply them.
In Photoshop CS4, you only have to apply the styles from the styles tab. If the Photoshop hasn’t shown the styles tab, make sure to show it first by clicking the tab Window > Styles. Then the styles tab will be shown.
Furthermore, if you want to add more styles, you just have to load them by clicking the small arrow down button at the right of the tab. Once it opens, you can see a lot of options, one of them is ‘Load Styles’. Next, all you have to do is load the styles from your computer folder and apply them to your work.