I don't really know how to make a QuickBMS script very well, but this should unpack the CGFX files from those OBT files.
Code:
# script for QuickBMS http://quickbms.aluigi.org
comtype DS_LZX
get OFFSET long
goto 0
savepos TMP
i = 0
for TMP < OFFSET
get OFF long
get ZSIZE long
get COMP long
savepos TEMP
Set P long OFF
math P + 1
goto P
get SIZE threebyte
goto TEMP
if COMP == 1
clog "" OFF ZSIZE SIZE
else
log "" OFF ZSIZE
endif
savepos TMP
math i + 1
if TMP >= OFFSET
break
endif
Next