in the AttributeEditor, you can define which rows should be shown and press the Update button in the panel on the left. You could of course also simply load the data and see if all data is there. Just run the process and check the meta data view and the data view.
The number of examples in the AttributeEditor is given as 19 (20 rows) maximum. If I open the dat file in a text editor I find all of the entries there. Could it be that there is an option preventing RM from showing all entries?
Another funny thing about it is that if i import my data to OpenOffice, export the data as XLS File and load this file as ExcelExampleSource I get all columns and rows.
If you have missing values in this data set at the end of the lines I would suggest upgrading to RapidMiner 4.2 since there was a bug for previous versions ignoring missing values at the end of lines in CSV files.
I have read some threads about that bug in other posts and I have switched to version 4.2.
Thanks for your help,