If you could find a consistent way to reproduce the issue, perhaps you could report it as a bug and provide Ashley with the capx and the reproduction steps so he can have a look into it.
Possibly it could be a case where a "big project" could cause the issue. But there must be clear steps on how to reproduce the issue all the time for the investigation time to be worth.
Now, are you sure also that "your serious project" is not just using too much memory ? Too large textures ?
Apparently you are using third-part addons, those cannot be accepted in a bug report. Does the issue still happen without them in the project ?
Also, C-7 mentioned "disabling" events, and you talked about "deleting". It's actually not the same thing.
Are you sure you tried the actual debuging solution proposed of right-clicking an event and "Toggle disable" it so that it is crossed.
The event is still a part of your project, not just "deleted". If the issue is about the size of the project/number of events, this could help pin point that issue.
You are the one who knows best the project so help out others helping you the more possible.
Moreover, doing such tests you can make sure you actually did not made some code mistake (inefficient loops ? groups that take too much action/CPU load ? ...) that you could actually correct on your own.
Finally this seem to happen on NW.JS preview, is it the same in a regular browser ? Previewing in browser and checking for errors in the browser does the console bring up more informations that could actually be useful ?
You can't just throw your project at someone, expect them to look at the code, understand it and debug it for you if you don't first dig up a bit what the issue could be as well. At least pinpoint where it is happening, under which circumstances, how to reproduce it on a consistent manner, so a logic can be made out of it.
Here's a rocket I've built myself.