What DNG compatibility option are you using in DNG Converter? In particular, did you try "4.6 and later" option?
Eric - just make it easier for you to reproduce the bug - here is the original .RW2 file (certainly ignore the quality of colorchecker shot in terms of how the target is lit, etc - it was not to make a profile actually - it was to illustrate the bug in question) = http://www.box.net/shared/f419prmuo2 ... and I am uploading the converted .DNG file too just in case = http://www.box.net/shared/gy5o9zzi57
bug is still there as of DNG converter v126.96.36.199
You need to choose the "Camera Raw 4.6 and later" compatibility option in the DNG Converter.
Many (not all) GH2 images require DNG version 1.3 which is not supported by the (older) DNG Profile Editor. The older DNG PE supports DNG version 1.2.
This will be rectified shortly, but in the meantime choose the above-mentioned compatibility option when building the DNGs for the purposes of using DNG PE.