Although I see you had some issues with the data being imported as dates, based on your follow up question, just wanted to comment on the size of the data that you’re importing.
Nine files with 6cols and 200,000 rows should be absolutely no problem with DataGraph. You should be able to bring in millions of rows and still the program should be pretty snappy.
FYI – in case you did not see this, you can drag and drop all nine files at once. Check out this demo video and about 2 minutes, you’ll see how to drag them all files in together, either as individual columns or in separate groups.
https://youtu.be/1e7fpf_-sns
Depending on what you need to do, you can also append all nine files in DG. You would place all the groups of data into one top level group and then use the Append subgroups option.
https://community.visualdatatools.com/datagraph/knowledge-base/append-groups/#append-subgroups
If anything seems slow, please let us know!