Is there a limit to the size of a formatted xlsx spreadsheet created by ColdFusion?

I'm using cfscript to create a (fairly) large xlsx spreadsheet.  As I was developing the script and the spreadsheet grew in size, I started getting the following error when attempting to open the spreadsheet:

I narrowed down the problem to my use of the functions used to format cells (specifically, SpreadSheetFormatCell and SpreadSheetFormatCellRange).  I found that by commenting out some of those function calls, the error would disappear.

After much trial and error, I've now come to believe that the issue isn't incorrect usage of the formatting functions, but rather some sort of internal limit I'm running into.  I threw together a simple test case to show this.  The following code (named "bigSheetTest.cfm" on my system) can be used to show the problem (at least on my machine):

<cfscript>
maxrows = 725;


formatBoldCenter = StructNew();
formatBoldCenter.bold = "true";
formatBoldCenter.alignment = "center";
formatBoldUnderlineCenter = StructNew();
formatBoldUnderlineCenter.bold = "true";
formatBoldUnderlineCenter.bottomborder = "medium";
formatBoldUnderlineCenter.alignment = "center";
formatNumber = StructNew();
formatNumber.dataformat = "##,####0.00";
formatMoney = StructNew();
formatMoney.dataformat = "$##,####0.00";

xls = SpreadSheetNew("Big Sheet", true);

row = 1;
bps = 30;

for(bp=1;bp LE bps;bp++) {
          col = 3*bp - 2;          SpreadSheetMergeCells(xls, row, row, col, col+2);          SpreadSheetSetCellValue(xls, "Reporting Period #bp#", row, col);          SpreadSheetSetCellValue(xls, "Current RG", row+1, col);          SpreadSheetSetCellValue(xls, "Hours", row+2, col);          SpreadSheetSetCellValue(xls, "Current OT", row+1, col+1);          SpreadSheetSetCellValue(xls, "Hours", row+2, col+1);          SpreadSheetSetCellValue(xls, "Current", row+1, col+2);          SpreadSheetSetCellValue(xls, "Cost", row+2, col+2);
}

lastCol = bps * 3;

row++;
SpreadSheetFormatCellRange(xls, formatBoldCenter, row, 1, row, lastCol);
row++;
SpreadSheetFormatCellRange(xls, formatBoldUnderlineCenter, row, 1, row, lastCol);

row++;

for(i=1;i LE maxrows;i++) { // 724 ok, 725 results in Excel error "Excel found unreadable content in 'bigSheetTest.xlsx'.  Do you want to recover the contents of this workbook?  If you trust the source of this workbook, click Yes."          for(bp=1;bp LE bps;bp++) {                    col = 3*bp - 2;                    SpreadSheetSetCellValue(xls, i*col/(i+3), row, col);                    SpreadSheetSetCellValue(xls, i*col/(i+4), row, col + 1);                    SpreadSheetSetCellValue(xls, i*col/(i+5), row, col + 2);                    SpreadSheetFormatCellRange(xls, formatNumber, row, col, row, col + 1);                    SpreadSheetFormatCell(xls, formatMoney, row, col + 2);          }          row++;
}

SpreadSheetWrite(xls, "C:\bigSheetTest.xlsx", true);

</cfscript>

Notice the "maxrows" variable at the top of the code.  When set to 724 (on my machine) the resulting spreadsheet may be opened without error.  However, if I change that variable to 725, Excel complains with the error "Excel found unreadable content in 'bigSheetTest.xlsx'.  Do you want to recover the contents of this workbook?" when I try top open the spreadsheet.  Any ideas on what causes this issue and how to avoid it?

If you are not able to recreate this problem with maxrows set to 725, try increasing the value until you get the problem.

Here are the specifics on my environment:

Windows 7 Enterprise (64 bit) with 8 Gig of RAM, Intel Core i7-3520M CPU @ 2.90GHz

Microsoft Office Professional Plus 2010

Microsoft Excel Version 14.0.7106.5001 (32-bit)