Try doing two or several masses, instead of one conglomeration. Copy the mass you have now to the clipboard, and then edit the mass to remove a portion of it. Close out of editing mode and check your warnings. If you still have the warning, continue editing the mass to remove portions until warning is gone. Then paste the mass from clipboard to the same place, and edit that mass, removing the portions you already have. Check your warnings again. If you need more masses to clear that warning, just keep building them from the clipboard copy.
