While checking the Coregistration step of PETsurfer using tkregisterfv, I encountered an issue (not sure if it was an error). The transform GUI simultaneously opened with freeview and I received this message in the terminal window ( warning : transformation can only apply to volumes for now. If your data includes ROI/SURFACE/WAY POINTS , please don't use this yet. INFO: LTA input is not RAS to RAS....converting...). What does this mean and how to I convert whatever input to RAS? mri_coreg finished without error and I want to make sure the pet image was properly coregistered with the anatomical. Please see the attached screenshot from terminal window. Thanks.