If you add those nodes to your flow and connect it to your data source, it should more or less work as is.
The simple time node adds msg properties for the current time, which you can then use as a time stamp for the log.
The switch / function nodes are likely used to format the text so it looks nice in the log.
The file out node stores this information in to a file of your choosing.
The file watch node checks to see if something has been added to the log file, and if it has then it triggers the exec node which is running a tail command on the file (which outputs the last lines of the log).
This then goes to the template node to display the info on the dashboard.
Set it up and have a go
If you get stuck then you can ask for specific help.
I tied and I just get stuck.
I have no clue for the function node. I would have used a template node to combine the simpletime and the payload for "on/off" - but there's probably someting to combine or instruct the save file node.