I am using Nevron Open Vision for .NET Enterprise 2017.1

I have a requirement to merge data from multiple tables in a dataset (c# DataSet class).
Additionally to merge all rows from a table in the dataset.
Does RichTextView support this type of merging/

If not can i write a custom mailmerge class derived from NMailMerge and NDataSource?
Or
Can i override or add custom types to the Insert Field dialog , and process these fields myself?

Thanks in advance
Mike Willis