I have some one...
I review sources (rc/services_ex.c) and understand - Oleg's firmware is not so cool for WL-HDD, becourse it oriented for no-HDD ASUS WL-hardware:
Service stupid-ftpd started only when USB-device attached to box (system search's for USB-storage in /dev/disks, and trying to mount them, IDE HDD presents in /dev/disks too; but if your attach not USB-storage device, firmware found only IDE disk and starts stupid-ftpd). This is not bug, becouse 1.9.2.7-3c more oriented for other hardware, but they opened many more feauters for WL-HDD and may be in newer versions this bug will be fixed (may be I rewrite code for WL-HDD, if will be free time for that)...