The steps detailed below will cause CC2 to locking up and stop responding when you export to the iC6.5 format.

PREPARATION STEPS:
1) Start a brand new project, using the default nude character
2) Open the Modify panel (if not already open)
3) Select an eye (CC_Base_Eye)
4) Open the Appearance tab of the Modify panel (the eye should still be selected)

THE CRUCIAL STEPS:
5) Activate the Appearance Editor
6) Select the >>CLEAR<< option for unused channels

CONTINUING WITH THE STEPS:
7) Edit the eye... I changed the Iris to a vibrant green color
8) You may Unload the Appearance Editor or leave it active, that doesn't matter
9) Export iAvatar
10) Select the "Character Creator 1.5 & iClone 6.5" format, leave all other options at Default values
11) Click the "Export" button

RESULT:
CC locks up and stops responding

DESIRED RESULT:
It should export the file.

OTHER INFORMATION:
a) In step #6 above, select the >>>KEEP<<< option, and the export will be successful.
b) In step #10 above, select the "CC2.0 for iClone (Beta) & iClone 7.0 (Beta)" option, and the export will be successful
c) EITHER "a" or "b" will make it successful, you don't need to do both