The MS Word template files (DOTX) are not supported in RadWordsProcessing. We have already logged a feature request and you can submit your vote for its implementation as well as track its progress through the related public item
I am not sure how it will fit your requirements but you can check the Mail Merge
functionality of RadWordsProcessing
. It allows you to create a document containing merge fields and populate them with different data. There is an example of this functionality
in the XAML SDK repository which may help you get a better understanding of the feature.
Hope this information is helpful.
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