It is not supposed to have any difference in RadDateTimePicker's behavior between a C# and a VB.NET project. I have prepared a sample application with two projects for your reference. In both projects, I use the free form date parsing and when I enter "1/3/88", January, 1st 1988 is set as value. If you are experiencing any further difficulties, could you please specify the exact steps how to reproduce the problem? Thus, we would be able to investigate the precise case and assist you further. Thank you in advance.
I hope this information helps. Should you have further questions I would be glad to help.