What's the name and location of the TMP files in question?  VFP uses temp files for several funcitons, but usually deletes them after the resource they support (for example a cursor) is destroyed.  Other temp files are deleted when VFP is exited.  What happens if you close FoxWeb?  Do these files go away?  In some cases, such as when a channel crashes, or is killed by FoxWeb, temp files are left behind.  This does not appear to be the case.  In these cases you would see entries in fw_start.log, indicating that the channel was restarted.