I have my options set to move large files to the end of the drive during defrag (Disk Images and Movie Files > 650 MB) which works just fine during a manual defrag. I also have scheduled Defraggler to defrag 'OS (C:\)' once daily at 8pm. However when that scheduled defrag is complete I can see that Defraggler put the large files back in the middle of the drive with the rest, as if ignoring the 'move large files to the end of the drive' option.
Defraggler v1.20.201 (64-bit)
Windows 7 Home Premium (64-bit)