How can I tell if I am over my flash size quota?

I want to know if I am going over my flash size quota. Where do I check this?

You can look at sections in your .out file

To do this, after compiling from the Tools > Code Gen... dialog, click the Download... button, then click the Coff Info... button.
You will see a new dialog that enumerates sizes of all code and data sections in your .out file. The interesting line is the bottom most line which gives totals like this:
Total memory used on target: Program = 4786, Initialized Data = 1252, Uninitialized data = 1466

The "Program" and "Initialized Data" will end up in flash. "Uninitialized data" must fit in RAM. For the example above you must have at least 6038 words of flash.