To All,
I tried all suggestions and nothing works, always shows I am using sample version.
Checked my Nuvi's ID, it was correct. Nobody informed what Jetmouse KeyGen to use, old 4 digit or new 5 digit with checksum. I tried both copying keys into notepad and saving as .unl, nothing worked.
Even tried SD card using SD cards 10 digit ID (Sandisk), that too did not work. Always the same saying I am using sample version.

Can anybody explain why after I delete the Lex_PKG folder from the Garmin directory on the Nuvi, then click on the Language Guide icon, it still shows sample version. How is that possible?