there are two things you need here, both are separate.
1) Show the Previous entry when validation fails.
For each form element, select it in design view. In the properties inspector, click the lightning bolt next to Initial Value. From the Dynamic data bindings list, expand the validated entries and select the coresponding item from the list.
2) Show an error message next to failed form elements.
Type the error message, the select it. On the server behaviors panel, click the plus button and select WA Validation Toolkit -> Validation Show If. From the list of validations, select the validation that should trigger the error to show. and click the plus button.
