This is similar for an idea I created for Inventor, but in my opinion it is even more valid for Inventor Read-Only.
For iAssembly member and iPart standard members, certain buttons are greyed out. In SDK terms these are the buttons with CommandTypesEnum kEditMaskCmdType and kShapeEditCmdType.
Unfortunately the buttons for section view and also setting components to visible or transparency seem to be defined that way. In Inventor Read-Only, there is no way to take a look inside an iAssembly member by hiding parts etc.
You cannot even create a new top assembly and place the member inside, which could be considered a cumbersome workaround.
In the Inventor idea there was another workaround proposed by changing the active member. This makes my Inventor Read-Only crash after "inital save" is called.
Regards
Erik