Each individual subject folder contains a file <subjid>.roiwise.stats.txt, where <subjid> should be replaced by your subject Id name.
This stats.txt file contains the surface areas for the cortical ROIs mapped by SVREG.
To get the index of the ROI and the label, you should look at
BrainSuiteXX/svreg/BCI-DNI_brain_atlas/brainsuite_labeldescription.xml
or
BrainSuiteXX/svreg/BrainSuiteAtlas1/brainsuite_labeldescription.xml
depending on the atlas used.
To perform a statistical ROI analysis in bssr, look at slide 42 onwards.