Darius - typically, parsing incoming data sets down to the useful rows is the job of 'upstream' data flow blocks like Source blocks (that can separate headers from raw data rows) and Operations blocks like Remove empty rows, Record filters etc.

Is this a Batch Append Source block looking directly at a folder of raw data files? What format are the raw data files in? .CSV? .XLS?

Sorry , yes Batch Append I meant and the files are in .XLS format.

You can configure the row numbers by selecting the "Excel" file type in the batch append block.