Strata scheme sux balls

We want to make over our bathroom to basically make it more user-friendly.  At the moment, it's a squeeze and we thought, hey, let's get rid of the shower stall.  But because we own a lot within a strata scheme, we basically only own the airspace trapped by the four walls, floor and ceiling.

So get this, we can't remove any tiles on the floor or boundary walls since it is common property.  And that means I can't remove the friggin' shower stall.  Why?  Because it's been bricked up and tiled over.  Yes, tiled over with tiles that we do not own!  

Is there a way around it?  Apparently one can apply to obtain exclusive use with a special by-law.  That has to be lodged at the Registrar General's Office.  Sheesh!