Hard to diagnose without seeing an image. A couple thoughts:
 1.) Can you send the output once you upgrade to the latest version, the text you included report v1.0.20190902, while the latest stable release is v1.0.20200331.
 2.) Is the image "Subj000396_09_cmrr_mbep2d_Mov4_TR1_cmrr_mbep2d_Mov4_TR1_00020.dcm" appreciably smaller than the other images from the same sequence that convert correctly? The most logical explanation for this error is that the file is corrupted (was not completely transferred). If the file is corrupted, you will need to export it again.
 3.) If neither of these solve your problem, I would need to see a sample to provide further feedback.