The database location you selected for your data table is set to USA, South Carolina. So, for each data point you're saving to Data Cloud, the signal has to travel twice from Japan all the way to South Carolina and back. And as more transactions are added to the pipeline with each slide, the backlog increases, which results in the user closing the browser window before all of the transactions are processed.
If you select the storage location in Asia (Singapore), there will be less distance between the user and the database which will result in faster transactions. Note that it won't let you change the location for an existing data table, you will need to create a new one at the new location. If this is an issue, I can make the change on my end, but you will have to delete all of the current data in the table.
Also note that you can change your default data storage location that will apply to all of your resources going forward, just look for the Data Governance section in your Account at
https://cluelabs.com/account/profile#account-data-governance