Hi Ecilia ,
It is possible to localize every single string to your own culture. You can access that string by using its text or caption properties. Please refer to the following KB article that demonstrates to localize all the text associated with Syncfusion controls.
http://www.syncfusion.com/support/kb/tools/Default.aspx?ToDo=view&questId=293Also please refer to our Localization Demo browser sample({Installation Drive}\Documents and Settings\{Username}\My Documents\Syncfusion\EssentialStudio\5.2.0.25 \Windows\Tools.Windows\Samples\2.0\Localization Demo\LocalizationDemo) for more details.
Please feel free to contact us if you have any problem to localize the Syncfsuion controls.
Thanks,
Nagaraj