I think I found a way do to this using that Event I mentioned (ModelingEvents.OnFeatureChange ). It was just slightly more complicated than I had in mind. I created an iLogic rule example, just for testing purposes, and it seems to be working just as planned so far in my testing. That Event is for every model document, across the whole application, the entire time Inventor is running, so I had to come up with a way to limit that to only focusing on one document, and only while that one document is open, then get rid of itself when that one document closed. So, this example includes 2 ways to get rid of the EventHandlers after they have been launched. One way is using an iLogic SharedVariable, where I can change the value of that from another rule, then run the original rule again which senses the changed value, then removes them. I have been using that method for years. The other one is subscribing to the DocumentEvents.OnClose event for that specific document. And when that event happens, it gets rid of the event mentioned above, and eliminates the OnClose one because the document is no longer available.
Next, I had to declare several variables between the routines, so that they would be held in memory while the EventHandlers were still running, and could hold on to a value between the 'before' & 'after' timing of the event, so that they could be compared to each other. Since this event gives us a reference to both the document and the feature, I first check if the document matches the one we want to monitor, and if not, it does not respond. Next it records the Feature.Adaptive status to those variables during both before and after timing, then compares the variables values during after timing to see if they are different. Then the code only responds when they are different. Then it just collects data from the 'Context' (none in this specific case) and writes a report about this event and the status change to the iLogic Log window. The whole part where it checks Context and writes a Logger report out could be replaced with a call to run an iLogic rule instead, or just put some simple code in there to do a task like what you are trying to do above.
The test code example is attached as a text file, because it is rather long. I did include a lot of comments in there, and left some of my other Logger statements in there, but commented out. You can get rid of those to reduce code size and clutter. If you have questions, feel free to ask them.
Wesley Crihfield

(Not an Autodesk Employee)