Only applies to Mac OS X Mountain Lion 10.8 (some earlier versions also).

There is an issue where Adobe InDesign crashes that has nothing to do with Grid Calculator Pro Edition. As a matter of fact it's a conflict between Apple OS and Adobe.

Here is an external link with more information: http://forums.adobe.com/thread/1024105?start=0&tstart=0

The crash occurs whenever 'Dont Show Again' warning dialog comes up in our plugin. This is an Adobe bug and you can check this even if our plugin is not installed.

Try this without using plugin & you'll still get the crash:
1. Create a new document and add pages.
2. Add some page-items on any page.
3. Delete the page having page-items.
At this moment, warning dialog must come up but instead, on mountain Lion, an empty dialog will come up & InDesign would crash.

*Update There's a fix for this now: http://helpx.adobe.com/indesign/kb/indesign-crashes-blank-dialog-boxes.html

If your issue is not related to the problem described in this article, it is suggested to read this article on how to reset Adobe InDesign.