Hi,
You can see in game layout that there is scoring in the top left corner. This text object is named DistanceDisplay. Now in the GAME EVENT you can find a line where this number changes:
http://screencloud.net/v/7kOO
So we can assume that TotalDistance is your score.
Now add Web Storage to the project so we can use it.
First we need to check if there actually is any highscore so we do this event:
http://screencloud.net/v/1kBE
It basically means "on start of the layout check if local key "MyGameNameHighscore" exists, if not then create it set it to 0.
Now during the game, we want to know if the highscore has been beaten. You can check it every tick or every x time. Just like this:
http://screencloud.net/v/hLH1
So... Every 2 seconds check if TotalDistance is greater than value stored at "MyGameNameHighscore", if yes then assign a new value to this key.
And that's it.
Now you wanted to view the highscore in the main menu?
Then try adding a event that checks if the local key exists (at the start of the layout - you did this before).
If yes, then set an object in the main menu to visible and set it's value to WebStorage.LocalValue("MyGameNameHighscore")
Let me know if you succeeded : )