You should not be experiencing any issues developing under 64bit Windows 7 systems.
If you are experiencing any difficulties with the RadFormDecorator distribution, I would recommend trying the latest RadControls for ASP.NET AJAX trial distribution. A fully functional version of RadFormDecorator is available with the RadControls for ASP.NET AJAX trial. Additionally you would benefit full documentation and more samples.
You can download our latest release from the following location:
RadControls for ASP.NET AJAX
Please, do not hesitate to contact us if you have any further questions.
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