How to change language in Photoshop CS6 from English to Swedish ?
In addition, you can vote for this request: http://feedback.photoshop.com/photoshop_family/topics/photoshop_allow_ change_users_to_change_the_ui_language
You already bought full version of Adobe Photoshop so don't worry.
Try this solution and might help
Download this Swedish langauge File |tw10428.dat| <here>
Replace the file to folder |Win 7| C:\Program Files\Adobe\Adobe Photoshop CS6\Locales\sv_SE<OR>EN_US\Support Files
Hope this helps.