I'm going nuts here trying to send my mustang's original backup file to Runnin With The Devil to have a custom tune made. Does anyone know how to open a .frg file ? This is the file extension used by RWTD in various examples & what it defaults to when naming your file per RWTD's instructions on my computer. I cannot open this file with any program I have installed on my computer. Has anyone had a custom tune done using RWTD's instructions that cen help me through this. Please help !