DeleteMIF setting problem

I just installed the new 54 mif2go in Framemaker 11. Using it with an older mif2htm.ini file that is local to the directory in which the output files are generated. In the Mif2Go Export dialog, I checked the "Delete MIF when done" box, then generated. However the MIF files were not deleted after Mif2Go finished. I tried manually setting DeleteMIF=Yes, but it gets reset to "No". Am I doing something wrong?

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[Setup]
UseExistingMIF=No
DeleteMIF=No
HTMLSuffix=.htm

Don't delete MIF

We've removed this feature for two reasons. First, it was intended to save disk space on systems from 1980; it isn't really needed with today's terabyte drives. Second, we need the MIF for test cases, and people were omitting it because it was getting deleted and they didn't notice. That doubled the support burden and wasted time for everyone. We change the setting to No so that people realize it is no longer available. Unfortunately, this change did not make it into the User's Guide in par. 5.1.3, "Reusing or discarding MIF files"; it will in the next upgrade.