Thank you for your question. TRi PLCs are designed for OEM equipment builders where protection of their intellectual property is important. As such there is no mechanism for pulling the program off the PLC internal flash memory back to a PC, therefore protects against unauthorized copying or modification of the control program. The OEM equipment builder is the entity that has the original source file.
i-TRiLOGI software also provides a tool for OEM to generate a compiled file (.CO5) which can be sent to the equipment user to load the program into a new PLC if a replacement PLC is needed. This could be a file that some OEMs may be willing to provide to their end customers.
You can however retrieve the program name, the date of file creation and file transfer by using the i-TRiLOGI software: "Controller->Open Matching Source File". With these information you can try to contact the supplier of the equipment to see if they are willing to provide you with copy of the program (it could be a .PC5, .PC6 or .PC7) or a compiled .CO5 file for your backup purpose.