LED1.write(1); save(); didn't save LED1 state after power off. why?

No it doesn't, It says:

save()
=undefined
Erasing Flash.......
Programming 3810 Bytes.......
Checking...
Done!
>BTN.read()
=true
>

and

>
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  1v44 Copyright 2013 Gordon Williams
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>

after reset button.