actually you can use MpWifi.Command Left
I've attached a sample group. If you have another scroll command already make sure to remove it. If you want to use a language other than English for the directions you need to use a payloadXML instead of the payload list I used in this sample.
If you want to adjust the speed of the scrolling you can do that by changing the loop delay in the command builder. I used 250 milliseconds. Also I arbitratily set the maximum loops to 60, but you could increase that if you want. I like to set a maximum so it won't keep going forever just in case something goes wrong...
