where is the temporary file stored?
for the boot (system) volume measurement (assuming your home directory is on the boot volume):
~/Library/Containers/com.katsurashareware.AmorphousDiskMark/Data/tmp/.us.katsura.adm-*
for the non-boot volume measurement:
<whichever-the-directory-you-selected>/.us.katsura.adm-*