Solution:

Please refer to the attached files. There're two command button, one for "save the value to file" and another for "load value from file". The pop-up message just for your reference, you can delete them freely. And our customer can modify the "load" function and paste them to "command on opening" section within "Picture", then each time we launch the AFX, we can get the previous value automatically. Combining the GS_MIN function (or GS_SEC, GS_HOUR, GN_MIN, GN_SEC, GN_HOUR) and "save" function, then we can update the value every fixed period automatically.