Data that has been previously recorded in Delsys Works software, can be exported as a *.csv file. This can be opened in Excel or similar and then saved as a *.txt file which can subsequently be opened by LabChart. This is achieved by opening LabChart, choose the File Menu>Open.... Here change the file type option to 'LabChart text file' or 'All files' and then select your file.
You should be aware if your original export had a time column or what the original data sampling rate was. Other limitations may be the number of available rows in Excel if your original file was very large.
More details about importing data files can be found in the LabChart Help Menu.