Spreadhsheet functions ROWS() and COLUMNS() don't work with external references, e.g. ROWS('file:///other.ods'#$Sheet1.A1:A3) should return 3 but returns error.
Fixed in master http://cgit.freedesktop.org/libreoffice/core/commit/?id=53b3df94dbd44b220f6531fe1cf2c83f3b1849d0 and libreoffice-3-5 http://cgit.freedesktop.org/libreoffice/core/commit/?h=libreoffice-3-5&id=f7e552b202dc1d155f731e3da18737ea6c13e75f