Please find my answers to your questions below:
- Multiline labels - feature will be available in the upcoming Q3 2014. For the time being you can use the workaround provided in this
- Series border - You can use the workaround from this
- Tooltips appearance options - You can use the workaround from this
- x-axis labels issue - Can you please elaborate more about this issue? What is the actual and the expected behavior form the x-axis labels?
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