In the export log you included, '-release-prompt-for-password:' (towards the end) should have been followed by an actual prompt in which you would have replied with the keystore password (the keystore itself is created, based on answers to questions displayed to the user, when attempting to export an android release build for the first time on a development machine).Were you prompted for the keystore password? Do you recall being prompted beforehand (perhaps days earlier) to create the keystore?
Regarding the empty screen issue, we are aware of such issues with Android 4.x, which were fixed in our latest version (currently 2.1.12) - see http://www.tersus.com/#Id=6424 and http://www.tersus.com/#Id=6491 for more details.
For details on how to upgrade to the latest version see http://www.tersus.com/#Id=239.
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