Pin Limit? Having problems displaying anything more than 20 - 30 pins.

My cache has write permissions, and it is generating fine, but there are occassions where I have many (30 +) pins, and the page will not load, nor will the cache get created.

Here is how I tested it.
1: Delete my "_promaps_geocache.xml" file from the server
2: Test a known result that shows 10 pins. This works great, "_promaps_geocache.xml" is re-created.
3: Test another known result that shows 10 - 20 pins. Works great, "_promaps_geocache.xml" has all the new entries added to it.
4: Try a known result with 30+ records, the map does not display, and nothing is added to the XML page.
5: Delete the XML page and try #4 again. The map does not display, and the cache page is NOT re-created.

For both #4 and #5, the page load is done almost immediately, but again, the map does not render and the cache is not created or added. It is as if Google is refusing to generate anything. Obviously, the cache cannot be created if Google does not respond the first time.

I came across this thread, and wonder if I might be having the same problem.
showthread.php?t=8702

I would love to know why this is happening, and how it can be corrected.