[Aaron]

This is a case where debugs might help you diagnose what is going wrong.

Try putting them into the code, like this:

debug "This is " & this.idstring
~Get our encumbrance level - if we're encumbered by that, or if we're wearing armor or shield, we're disabled
   if (hero.tagis[Encumbered.Light] = 0) then
debug "We have no Encumbered.Light tags, so we should disable ourselves and end this script early"
      perform assign[Helper.SpcDisable]
   done
   endif

   ~If we're not shown, disabled or the first copy, get out now
   doneif (tagis[Helper.ShowSpec] = 0)
debug "We are high enough level to get this ability, and have Helper.ShowSpec, so we passed the first gate"
   doneif (tagis[Helper.SpcDisable] <> 0)
debug "We have no Helper.SpcDisable tags because nothing disables us, so we passed the second gate"
   doneif (tagis[Helper.FirstCopy] = 0)
debug "We have Helper.FirstCopy tags because we are the first active copy of this special, so we passed the third gate"

   ~assign our climb speed and climb skill bonus
debug "hero.child[cMnkSpeed].field[xCount].value is " & hero.child[cMnkSpeed].field[xCount].value & ", so before adding our bonus #value[xClimb] is " & #value[xClimb]
   #value[xClimb] += hero.child[cMnkSpeed].field[xCount].value *10
debug "After adding our bonus #value[xClimb] is " & #value[xClimb]

debug "before adding bonus, hero.childfound[skClimb].field[skTotal].value is " & hero.childfound[skClimb].field[skTotal].value
   #skillbonus[skClimb] += 8
debug "After adding bonus, hero.childfound[skClimb].field[skTotal].value is " & hero.childfound[skClimb].field[skTotal].value

Then go to Develop -> Show Debug output, and look at the window that pops up. Each debug has it's own line, so you can tell where the eval script gets hung up (if some are not showing) and adjust the priority + reload.