Yes the ZipSeam is washer and dryer safe, though it may come loose under heavy duty spin cycles.
You can easily remove the ZipSeam from your fitted shirt by pulling the cord. You can then reuse the ZipSeam for a better fit or to use on a whole new shirt altogether. I have used the same set myself for the past 2 years!
Unfortunately due to the thickness of the suit fabric and the many layers, it is not advised to tailor a suit with the ZipSeam
Technically you can tailor anything with the ZipSeam as long as the fabric is not too thick to squeeze into the channel. Ultimately, the thicker the material the more difficult it will be to install the ZipSeam