Before starting your simulation, you have to click on "Control output" (Run-> Start simulator menu).
Then "Record complet data..." (the second choice in DATA TO FILE menu) has to be checked.
Choose the destination file.
Then you can create a .pow file of the time steps you want FEFLOW to save your results.
You can load time steps by clicking on "Edit time stages for which saving is desired".
I hope I understood you question and I gave you useful advice.