Hi,
I am using mac os 10.10.5 and mricron 30Apr2016. mricron freezes when I try to save a multislice bmp using a template from the FSL directory (e.g., MNI152_1mm_brain.nii.gz) and 2 overlays.  It saves just fine when I use a template provided by mricron (e.g., ch2better.nii.gz) and the same two overlays.  

Any suggestions? Other than use the ch2better.nii.gz template :) 

Thanks,
Scott

Fixed in latest release.