Thanks, but that error doesn't always appear. Here's the log from the Customization I attempted right after I flashed, no errors with GDFS this time around:

16:15:57|
16:15:57| Attempting to open the interface...
16:15:57|
16:15:57| TURN OFF PHONE!
16:15:57| Hold 'C' button on phone and connect phone NOW.
16:15:57| You have 30 seconds...
16:15:57|
16:15:57| Baseband ID: 8040
16:15:57| Protocol Version: 3.1
16:15:57|
16:15:57| Sending db2010_cid00_prodid_p3l.bin...
16:15:57| Applet ID: 061113 1250 ALUCXC125872_COMPACTPRODUCTION_ID_LOADER P3L
16:15:57| This is a PRODUCTION_ID loader
16:15:57| Activating GDFS...
16:15:57| Cannot open GDFS
16:15:57| Activating GDFS...
16:15:58| Phone name detected!
16:15:58|
16:15:58| Profiling SEMC phone...
16:15:58| Platform: DB2010
16:15:58| OTP CID: 49
16:15:58| EROM CID: 49
16:15:58| EROM Color: Red
16:15:58| IMEI: 35906100xxxxxx
16:15:58| Phone ID: W810
16:15:58| Region: S_ASIA_LEVAN
16:15:58| CDA: CDA102555/110 R2A
16:15:58| Firmware Version: R4ED001
16:15:58| EROM: n/a
16:15:58| Ready for operation!
16:16:02| ~~~~~~~~~~ Custpack information ~~~~~~~~~~
16:16:02| Custpack: EUROPE_1 (CDA102494/108) (W810)
16:16:02| Generic(non-branded) custpack: Yes
16:16:02| Allowed languages: en, pt, es, fr,
16:16:02| ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
16:16:09| ~~~~~~~~~~ Custpack information ~~~~~~~~~~
16:16:09| Custpack: AMERICA_2 (CDA102494/76) (W810)
16:16:09| Generic(non-branded) custpack: Yes
16:16:09| Allowed languages: en, pb, xl,
16:16:09| ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
16:16:18|
16:16:18| Sending db2010_cid49red_cs_r3a010.bin...
16:16:19| Header: Error 0x10
16:16:19| Error: Customizing failed.
16:16:19| Error: Flashing failed
16:16:21| Disconnected... Unplug the phone
16:19:40|