Hey Crown,
We put some new infrastructure in place for PingPlotter v5's web interface, and the feature to make it read only (which was a customization we added in later on in v4) has yet to be developed. This feature is absolutely in the works though (we're hoping to have it implemented in a future release).
If you should find that this functionality is something you require in the short term, PingPlotter v4 *does* still have this ability (and can actually be run side-by-side with v5).
If you have any other questions - please let us know!
Best wishes,
-Gary