WowAce

What steps will reproduce the problem?
Checked Unit Configuration->Player->Enable Holy Power Bar

What is the expected output? What do you see instead?
SUF is throwing a LUA error.  The player frame ends up in a mildly bad state--doesn't update, doesn't show the holy power bar--but it seems fine again once I uncheck the holy power bar option.  The AceGUI embedded in ButtonFacade should be the same version as in r9.

What version of the product are you using?
r9

Do you have an error log of what happened?
Message: ...rface\AddOns\SimplisticUnitFrames\modules\layout.lua line 441:
   attempt to compare number with nil
Debug:
   (tail call): ?
   ...rface\AddOns\SimplisticUnitFrames\modules\layout.lua:441: PositionWidgets()
   ...rface\AddOns\SimplisticUnitFrames\modules\layout.lua:113: Load()
   ...erface\AddOns\SimplisticUnitFrames\modules\units.lua:225: SetVisibility()
   ...rface\AddOns\SimplisticUnitFrames\modules\layout.lua:94: Reload()
   SimplisticUF_Options\config.lua:206:
      SimplisticUF_Options\config.lua:196
   SimplisticUF_Options\config.lua:241:
      SimplisticUF_Options\config.lua:222
   (tail call): ?
   [C]: ?
   [string "safecall Dispatcher[2]"]:9:
      [string "safecall Dispatcher[2]"]:5
   (tail call): ?
   ...nfig-3.0\AceConfigDialog-3.0\AceConfigDialog-3.0.lua:797:
      ...nfig-3.0\AceConfigDialog-3.0\AceConfigDialog-3.0.lua:612
   (tail call): ?
   [C]: ?
   [string "safecall Dispatcher[3]"]:9:
      [string "safecall Dispatcher[3]"]:5
   (tail call): ?
   ...e\AddOns\ButtonFacade\Libs\AceGUI-3.0\AceGUI-3.0.lua:314: Fire()
   ...de\Libs\AceGUI-3.0\widgets\AceGUIWidget-CheckBox.lua:68:
      ...de\Libs\AceGUI-3.0\widgets\AceGUIWidget-CheckBox.lua:57

I can't reproduce your error. Have you imported old settings?