Ideally, this would be a simple single line fix, but looking into this, that does not appear to be the case. Save and Save As specifically save a JMP data table, as beyond the path/filename, there are no additional parameters for those functions, such as file type. There is another file output function, Save Text File, but it only outputs a specific string to a text file. Fortunately, I have considerable programming experience, so the method for accomplishing this task was rather straightforward to me after giving it some thought, as most programming languages would create a CSV file in this way.
Below is a script that accomplishes what you want, you would just need to adapt it to your data table; you would need to specify your particular columns in your data table. What this script does is first determine the number of rows in the data table. Then a For loop is used to capture data from specific columns in each row in the data table and write it to a text file. On the first row, a new file is created or an existing file is overwritten. For all remaining rows, data is appended to the existing file. Also, so you do not wind up with a file that is just one continuous line of data, line feeds are added to all but the last row in the file.
The one advantage of having to write text files in this way is that you can choose which columns to export if you only want certain data. Obviously, this process is tedious if you want all of your data and you have several columns, but as I mentioned earlier, this technique is typical in most programming languages.
Names Default to Here(1);
dt = Current Data Table();
lastRow = N Rows();
For(i = 1, i <= lastRow, i++,
//get columns
location = :Location[i];
day = :Day[i];
time = :Time[i];
count = :Count[i];
mean = :Mean[i];
max = :Max[i];
//create comma-delimited row
csvRow = Concat Items(
{location, Char(day), Char(time), Char(count), Char(mean), Char(max)},
","
);
//save row to text file
If(i == 1,
Save Text File("$DESKTOP/Test File.csv", csvRow, Mode("Replace")),
Save Text File("$DESKTOP/Test File.csv", csvRow, Mode("Append"))
);
//export line feed for all but last row
If(i != lastRow, Save Text File("$DESKTOP/Test File.csv", "\!n", Mode("Append")));
);