The data mode refers to how data is collected. By default it will collect based off of the amount of time since the start. Events with entry allows for capturing specific data points and allows you to enter an X coordinate for the point. In timed mode, you can change the length of the run and the frequency of the sampling. In events with entry, you can choose the X column name. Full spectrum is used with a spectrophotometer and will record absorbance for various wavelengths.
To collect individual data points in events with entry mode, click on the Capture button. This will allow you to enter an X coordinate and save the data point.