[Freesurfer] Converting V1 labels to nifti

Dear Freesurfers,

I would like to use V1 labels (created with the Hinds method) for a ROI-based analysis on data analyzed with FSL FEAT using FSL featquery. I have not run a full recon-all segmentation, only recon-all -s subjid -label-v1

I need to convert the labels to nifti volumes while registering to MNI standard space. I guess the right command would be something like mri_label2vol --label lh.v1.predict.label --reg register.dat --hemi lh --subject subject --o lh.v1.predict.label

Is there a register.dat from the FSL feat directory that I could use for this?

Anything else I need to add? Of course, I would like to keep the resulting volume probabilistic.

All the best,

Anders