Simply copy the file to the folder where TomTom_Navigator.exe (or TomTom Navigator.exe) is and launch this application instead the real TomTom.
The idea behind this file is that the lag is caused due to the full CPU usage of TomTom navigator that leaves few or even none CPU time to the GPS drivers. This bot launches TomTom and then reduces the TomTom process priority. The bot itself unloads from memory when TomTom exits.
I have tested it and seems that works Ok, but I want your opinions before making a good icon for it (icon designers wellcomed )
In order to make the program more general, I've created GPSBot that works in the same way but have a GPSBot.txt file with the name of the program to be launched between colons. As an example the zip contains a file with "TomTom_Navigator.exe". This version also needs to be copied to the same folder than the executable in order to allow to have several copies for different programs.
Download it from my page: http://beemer.sesma.eu/en/gpsbot.htm