Google Spreadsheet - Excel Export Compatibility Issues

In Google Spreadsheet, the function ROUNDUP expects two parameters - the value and number of digits. But the second parameter is optional, defaulting to 0. If you had given just one parameter for the function, it works fine until you do an excel export.

In Google spreadsheet, the formula was:

=IF(ROUNDUP('Sheet1'!B52+'Sheet2'!B52+'Sheet3'!B52)-'Sheet4'!B51>='Sheet1'!B52,'Sheet5'!$E53,0.0)

In the exported excel, it came out as

=IF(((ROUNDUP((('Sheet1'!R[24]C+'Sheet2'!R[24]C)+'Sheet3'!R[24]C))-'Sheet4'!R[23]C)>='Sheet1'!R[24]C),'Sheet5'!R[25]C5,0.0)

Really weird export. It took me a while to suspect that the missing parameter was causing the problem. Once the parameter was supplied, the exported excel looked fine.