Hello,
You can set "Choose source type -> SQL -> Debug" parameter to "Yes" to find a problem with DB connection.
About CSV files, the extension doesn't support ability to show data from MS Excel files (.xlsx). It can show data from CSV files. If file is located in Joomla! sub-folder, use the following value for "CSV -> Path to CSV file" parameter:
images/Documents/testcsv.csv
Check that the path is correct (it is case-sensitive). If it doesn't help, could you send screenshot(s) of module settings page and CSV file by
email?
Regards,
ARI Soft