Change Grid Type value or its instance's Extents through API?

Hi, is it possible to control the parameters of Grid type and its instances value via API?

I currently have two questions about Grids,

I've tried using Get_Parameter and SetValueString but couldn't make them work.

1. According to this post, only Continuous Center Segment can be dimension reference.

so how can I change the type value to Continuous for dimension,

then change the value back to its default after dimension finished?

https://forums.autodesk.com/t5/revit-api-forum/fail-to-get-reference-for-grid-for-dimension-in-2017/td-p/6636474

2. Sometimes the extents 2D/3D switch symbol get stuck while turning on/off the crop view

how can I reset its value through API?

Thanks in advance.