Here is a selfwritten routine ReadExcel() which conveniently does the reading of the whole sheet and subsequent submatrixing and uses a syntax similar to READEXCEL. Its a quick hack without any error checking, but at least it covers the full range of cells Excel offers (also double letter columns) and accepts upper and lower case letters.
Guess this should work in MC14 as well. A possible limit can be if the sheet is that large so Mathcad can't temporarily store it in memory. But I guess Mathcad should be able to cope with most Excel sheets.
