Hi Venkat
I think of following options -
1. I know using some authorization object you can eliminate(hide) pencil icon(Change Mode) from planning book. Please take help from your security personnel to find out the authorization object.
2. In design view of planning book, you can make KF as Output only.
3. Or you can use ROW_INPUT(KF Name) function to make keyfigures non-editable.
Hope this will help
Thank you
Satish Waghmare