Hi Clement
As described by @jacob.small in this post: Create Material
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The Dynamo Player behavior actually makes sense when you think about how it runs under the hood. Each time the player is run it
Opens the graph
Finds the editable inputs
Asks the user to give a value for each input
Runs the graph
Closes it the graph
Once that runs the user is asked if they want to open another graph and start the process over again. Inputs are reset and created elements are maintained as a result
"