2018.2

"rotate": true,
...
}
Properties of the Legend (listed here: https://docs.amcharts.com/3/javascriptcharts/AmLegend)
should go in the legend section in the JSON:
...
"legend": {
"position": "right"
},
The Source tab also lets you change properties that are available in either the Script Wizard or
other tabs of the Chart Properties dialog. You could, for example, set the colors of the bars,
lines or slices by adding an array of hexadecimal color values, like this:
"colors": ["#FF6600", "#FCD202", "#B0DE09", "#0D8ECF"]
Note that properties defined on the Source tab override those made in the Script Wizard or on
other tabs of the Properties dialog.
For inspiration you could use amCharts' online editor: https://live.amcharts.com/new/.
Properties can be copied directly from the Code tab in the live editor to the Source tab of the
Chart properties dialog in Connect.
Note that copying the entire content of the Code tab will also carry over the sample data from
the live editor (the dataProvider key). These will be overwritten by the chart script in Connect.
Note
l Properties defined on the Source tab override those made in the Script Wizard or on
other tabs of the Properties dialog. The only exception is the dataProvider
property: this will be overwritten by the chart's script.
l In Connect, the implementation was tested with Pie Charts (amPieChart) and with
Bar Charts and Line Charts (amSerialChart). Other variants may or may not work.
l Animations will not work in the output, even if the output is a web page. This is
because the chart is generated on the server, not in the browser.
To get animations to work you would have to implement a solution similar to the
one described in this How-to: Dynamic dashboard charts.
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