[Samsung Galaxy Mega] ponglenis:
Well, i analyzed what we have and come to the following conclusions:

1. [MENTION=1007351]locuter[/MENTION] thanks for posting that information! I'm not sure if the posted log is actually a CWM log though. This date put me off:

Starting recovery on Tue Jan 1 00:58:03 2013

Also, it logs out this command, which looks like an update script:

Command: "/sbin/recovery" "--update_package=CACHE:recovery/sec_csc.zip" "--carry_out=csc_factory" "--wipe_data"
previous_runs = 0
send_intent = (null)
update_package = CACHE:recovery/sec_csc.zip
att_fota_update = 0
tmo_fota_update = 0
wipe_data = 1, wipe_cache = 1,wipe_sdcard = 0,delete_data = 0,wipe_data_crypto = 0,wipe_carrier = 0,no_wipe_custom=0
wipe_hdd_secure = 0
show_ui_text = 0
update_factory_csc = 1, update_home_csc = 0, factory_fota = 0
carry_out = csc_factory
tima_kernal_recovery = 0
(replacing path "CACHE:recovery/sec_csc.zip" with "/cache/recovery/sec_csc.zip")

And later proceeds to install the update:

Installing update...
minzip: Extracted file "/system/CSCVersion.txt"
minzip: Extracted file "/system/SW_Configuration.xml"
minzip: Extracted file "/system/VODB/de_DE/checked"
minzip: Extracted file "/system/VODB/de_DE/de_DE-ak-cur.lite.res"
minzip: Extracted file "/system/VODB/de_DE/de_DE-lk-text.lite.res"
minzip: Extracted file "/system/VODB/de_DE/de_DE.lang"
minzip: Extracted file "/system/VODB/de_DE/files.txt"
minzip: Extracted file "/system/VODB/en_GB/checked"
...

So my guess is this file was written by the stock recovery.

CWM *should* also write this file as soon as the recovery starts, or am I mistaken? I pulled the log from my N7000:

chris@cms:/cms_android/1_i9205/cwm_recovery_last_log$ cat last_log.n7000 | grep -A 20 Starting
Starting recovery on Tue Jun 4 18:18:00 2013
(GMT)framebuffer: fd 4 (800 x 1280)
PhilZ Touch 4
CWM Base version: 6.0.3.1
I:Build version: 4.93.6 - n7000
recovery filesystem table
=========================
0 /tmp ramdisk (null) (null) 0
1 /boot emmc /dev/block/mmcblk0p5 (null) 0
2 /recovery emmc /dev/block/mmcblk0p6 (null) 0
...

[MENTION=1007351]locuter[/MENTION] Did you flash CWM, enter the recovery, then cat the file? In any case, having the log file from the original recovery might still come in helpful, as it can give hints.

2. I looked through the last_log and tried to find anything that looks familiar to the graphics.c from the CM GitHub. The only thing referenced was this:

last_log:

[initialize ui and event]
initalized graphics for qualcomm.
pixel format -> GGL_PIXEL_FORMAT_RGBX_8888
return for qualcomm. double_buffering = 0
framebuffer: fd 4 (720 x 1280)
not turn off screen

In graphics.c, the value gets checked for when calling:

static int get_framebuffer(GGLSurface *fb)

else if (PIXEL_FORMAT == GGL_PIXEL_FORMAT_RGBX_8888) {
vi.red.offset = 24;
vi.red.length = 8;
vi.green.offset = 16;
vi.green.length = 8;
vi.blue.offset = 8;
vi.blue.length = 8;
vi.transp.offset = 0;
vi.transp.length = 8;
}

Well, that's all. I just wanted to do a little digging. Maybe someone who knows more about recoveries and/or how the framebuffer works (if it is even the problem) can look if the graphics.c from CM-Github can be modified and used for the 6.3.

One last thing:

If one of you guys do manage to pull a CWM recovery log, i'd be more than happy to check it out for clues.