Some Profurl have a two-piece drum (the plastic bit). If, so, you can prolly separate that from the bearing pack and not have to take it all down.
But if you want to remove the whole thing, bearings and all... Yes, you have to tie off the mast
- you're effectively removing your forestay. In fact, I'd use two ties... jib
and spinnaker/screacher halyards will do the job. Run them both to your forward beam and snug 'em good, enough to slack the extrusion and drum. You might have to slack your shrouds to do it, depending on how tight you can get your halyards.
I had my Profurl rebuilt via the rigger (a dealer). My guy was Charlie Taylor of Bay Area Rigging
in Deltaville VA