Hello faspial,
Welcome to our forum and thanks for contacting us with your question!
I'll start with excessive decimal places. There's an API option
tooltip.valueDecimals that allows you to specify how many decimals to show. It should be perfect in your case.
API reference: https://api.highcharts.com/highstock/to ... ueDecimals
When it comes to missing series for SMA, it is hard to tell what is not working without looking at you code. It would be great if you could try to reproduce that issue in a form of a live demo. You could start here:
https://jsfiddle.net/BlackLabel/6q07mjv5/
Here you can find working demo, perhaps comparing it with your code could give you an idea what's wrong:
https://jsfiddle.net/BlackLabel/ztyvefp8/
Let me know if that was what you were looking for!
Best regards!