Excel Reports Error Reporting-- When running with nothing in "location of time field" get a NullPointerException

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Heya--

The title says it all. It appears that if you leave the "location of time field" blank, Mango throws a NullPointerException. It seems the other required values there tell you that they are required, rather than tossing NullPointerException.

Next time you go through updating the Excel Reports module, maybe have a quick look at the error handling to get the "location of time field" caught if it's blank.

This is in Mango 3.6.5

I looked into this and you only get a NullPointerException when you are using a rollup. I'm not sure if this is by design or not. @terrypacker can maybe confirm this. But ye a better error message would be helpful