Some info from the manual
2.4.7 Track Logs
NavNGo iGO 8 can log the track that you drive (page 47).
A Track Log is a recording of how your GPS position changed and it is independent of the route NavNGo iGO 8 calculated.
Track Logs can be recorded, renamed, replayed, shown on the map, exported to a memory card in GPX format, and deleted. See page 71.
Independently of the normal track log, you can instruct NavNGo iGO 8 to record the native GPS data received from the GPS device. These logs are saved as separate text files on the memory card, and they cannot be shown or replayed in NavNGo iGO 8.
Recommend you read this manual
http://www.navngo.com/content/language/eng/dl/UM/iGO8_R3_PDA_UserManual_UK.pdf and it appears you need a memory card in the device