Currently we don't have Binding properties for the RadMaskedInput control. I filed a feature request for this. You can track its progress here: Public URL
The workaround is to bind your data directly to its child TextBox or to convert the step that types in the RadMaskedInput into coded step and attach the data column in code
. See this video
for a quick demonstration of both approaches.
Regarding the date picker issue, you should be able to bind your data to the TypedText Binding property as seen in this video