Integration document Conversion

Appian only supports these file extensions, so probably you need to change the file format and then expose it over your network. 

PDF, JPG, GIF, PNG, KML, KMZ, SHP, DOC, DOCX, XML, XMLX, XLS and XLSX.

Appian can convert base64 or binary files to Appian document

Or you can build custom plugin to handle this file type

What exactly do you mean with "Can Appian Integration convert .rpt file to Appian document"? Appian will happily store any kind of document.

Since Appian only accepts specific file extensions, you must probably change the file format before making it available across your network.

XML, XMLX, XLS, and XLSX, as well as PDF, JPG, GIF, PNG, KML, KMZ, SHP, and KML.

Base64 or binary files can be converted to Appian documents by Appian.

You might also create a custom plugin to deal with this file type. study in new zealand really help me in this.