"If you prefer to combine MNI-space ROIs with your surface-based analyses then typically you would want to define an additional MNI-space dataset in Setup.Functionals pointing to your MNI-normalized functional volumes and then make sure that the MNI-space ROIs are being extracted from that new dataset instead (e.g. select 'extract from dataset-2' for those ROIs in the Setup.ROIs tab), while the surface-based ROIs are being extracted from the original dataset (e.g. select 'extract from dataset-0' for those ROIs)"