Can somebody tell me where CRC checksum values of CHD files are stored?
I made a -listxml file but I don't see it in there.
The CRC and SHA1 checksum values of ROM files however are stored in this XML file.
CRC32 is not used to determine validity of a CHD - only SHA1 is. The SHA1 listed in various MAME outputs (-listroms, -listxml) is taken from the data inside the CHD, not the CHD file due to various compression options available. Whatever XML file you are using shouldn't use CRC32's because they are not provided by MAME source, only the SHA1's are.
<disk name="area51" sha1="3b303bc37e206a6d7339352c869f050d04186f11" region="ide:0:hdd:image" index="0" writable="yes"/>