Unfortunately, CHDK "CRW" is just a framebuffer dump, without any meta data. So you can't recover that from CHDK. It is *not* in Canon's actual CRW format.
http://chdk.wikia.com/wiki/DNG4PS-2 may be able to convert it to dng for you. If SX1 is not in the camera list, you can manually add a profile as described in http://chdk.setepontos.com/index.php?topic=6754.0
If you have the matching jpegs, the meta data will be included in the DNG.
edit:
Alternatively, ufraw http://ufraw.sourceforge.net/ rawtherapee http://rawtherapee.com/ or other dcraw http://www.cybercom.net/~dcoffin/dcraw/ based programs may be able to open your CRWs, although you won't get the meta data.
Since SX1 allows one to create raw files without CHDK, I mistakenly assumed that the default raw setting for CHDK would yield Canon raw files, rather than CHDK raw files. Otherwise I would have picked the DNG format in the CHDK settings, so I could easily import the raw files in ACR.
Problem is I have no idea where to find the specs for the SX1 similar to these specs (for using DNG4PS-2):
Camera Name: Canon IXUS 120 IS ------ CHANGE TO YOUR CAMERA NAME
Short Name: IXUS120IS -------CHANGE TO YOUR CAMERA NAME
Sensor Size: 4080 x 3048 -------CHANGE TO CORRECT VALUES FOR YOUR CAMERA
Jpeg Size: 4000 x 3000
Active zone x1, y1: 52, 14
Active zone x2, y2: 4052, 3014
Black-white levels: 127 - 4095
Mosaic type: Red, Green Green, Blue
Bits per unit: 12 bit
----
I've tried all the other raw programs like rawtherapy, ufraw, dcraw, etc.. but none of them worked.
Too bad CHDK doesn't allow an in-camera conversion from CRW to DNG (similar to the way it allows one to
develop the CRW file in the camera to yield a JPG). Though of course I do have the associated JPG for the CRW I'm
trying to convert to DNG.
