We had a small problem with the Turkish localization, which is fixed in the service pack. In a few days we will make an upgrade of our Documentation Portal and you wont have any problems accessing it.
Unfortunately we do not have the developers guide as a pdf file but we changed the localization culture of the Documentation Portal to English, so I think you will be able to open it now.
I will write to you when we have made the upgrade.
If you have any other problems do not hesitate to contact us.
the Telerik team
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