Can you please let us know in some further details what are the problems you are currently encountering when you follow the mentioned forum thread?
Are you able to successfully create the new dynamic field int eh Subscriber object (you can verify this by running your code in debug and then also checking the database table as outlined int he forum thread discussion).
If the above stage is passed successfully, are you experiencing some problems modifying the default SubscribeForm template?
the Telerik team
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