Excel 2010 Ran out of resources while calculating error (but not in 2007)

I have a formula that works in Excel 2007, but when I load it into Excel 2010, I get this error:

"Excel ran out of resources while attempting to calculate one or more formulas. As a result, these formulas cannot be evaluated."

Here is the formula:

Please Login or Register  to view this content.

What it's doing is reading values in a column, which may have blank entries in between values and/or a variable number of entries, taking only the bottommost 20 values, then finding the smallest 10 of those, and averaging them for the result.

Does anyone have any ideas on how I can fix this?

Thanks!

I'm attaching the spreadsheet in question. I'd really appreciate any help that I can get on this, as as solution has proven to be most elusive.

Thanks!

Sorry to say, Excel 2010 is not quite a stable product, yet.
Quite often I have to revert to Excel 2007.