If you are driving your motorhome in UK you may want to configure TomTom to avoid our small/narrow country roads and use A roads / Motorways instead, alternatively if you are abroad in say France you may want to avoid the expensive Toll Motorways and use smaller roads instead, this is quite easy to do as follows:-

Instructions based around V2.24 (build 361)

Go into TomTom Navigate mode, then touch screen to access config menus
Go to Advanced Tab and scroll down to the 'Preferred Speeds' Section.
If you want to avoid the motorways just enter a speed of '0' mph for them or if you want to avoid country roads then enter '0' for their speed setting.