Modifying PDF with SDK

Hello,

I have some questions, I would be thankful if someone could help me:

1- when I open the ActiveView sample from SDK (Adobe DC) on windows, the selected pdf is not rendering properly, Do I need to do anything to get it to work without any issue? and when I click on comments the application stops working. Here is the Screenshot.

2- How Can I extend the ActiveView sample to have the commenting toolbar (including the drawing tools like line and etc...)?

3- Can I add line to pdf file through SDK classes?

4- Can I Enable commenting toolbar in Acrobat ActiveX control or is there any other control from Adobe Acrobat pro to use with commenting toolbar enabled?

Thanks,