Hi, We are using "Text Doc from Template" Appian smart services,

Were you able to find a solution? Have you checked out the documentation here:
forum.appian.com/.../Text_Doc_From_Template_Smart_Service.html

Some things that stick out:
* The supported file extensions include XML, CSV, RTF, TXT, or XLSX
* The template must be encoded in UTF-8 for Unicode characters to appear in the document

I've also seen different editors handle Unicode characters differently. For instance, Notepad++ will usually display Unicode characters as expected for just about any file, but MS Excel requires that the file start with a special hidden BOM character to open some .CSV's.

Hope that helps.