How to create an ability that must be activated
 

I've created an ability that is supposed to require a Swift action to activate, and it's supposed to give a bonus to AC for 1 round when activated.

However, though I used scripts from the Magus Spell Shield ability, it doesn't appear in my character sheet as something that can be activated.

I can see the text describing it in the special abilities section, but I can't use it and get the desired bonus to AC.

Did you click on "Show in Activated Abilities List?" etc, under Activation Information. Do you have a script that copies the activation information from Spell Shield?
ie:
~ If we're disabled, do nothing
doneif (tagis[Helper.SpcDisable] <> 0)
doneif (field[abilActive].value = 0)
#applybonus[tACShield, hero.child[ArmorClass], field[abValue].value]

So in the main menus on the GUI, I've picked:

Action: Swift
Range Measure: Personal
Duration: 1
Duration Measure: Round
Section 3 -In-Parenthesis: Include Duration Text
Statblock Line: Spell-like Ability

Show in Tracked Resources List (checked)
Automatic Calculations: 3+Attribute Mod
Charge Calc Attribute: Charisma
Usage Period: uses/day

Then, among the blue buttons at the top right, I've got:

Fields
FieldID: abDuration, Value: 1

Eval Scripts Phase - Final Phase, Priority 1000, Index 3

~ If we're disabled, do nothing
doneif (tagis[Helper.SpcDisable] <> 0)

doneif (field[abilActive].value = 0)

~ if not mythic, get out
doneif (tagis[LGMyClass.?] = 0)

perform assign[Usage.RoundsAbs]
field[trkMax].value += field[abDuration].value

if (field[abilActive].value <> 0) then
perform assign[User.Tracker]
endif

Eval Scripts Phase - Post-attributes, Priority 10000, Index 1

field[abValue].value += round(hero.tagcount[Classes.Sorcerer]/2,0,1)

Eval Scripts Phase - Post-attributes, Priority 20000, Index 2


~ If we're disabled, do nothing
doneif (tagis[Helper.SpcDisable] <> 0)

doneif (field[abilActive].value = 0)

#applybonus[tACDeflect, hero.child[ArmorClass], field[abValue].value]

#applybonus[Bonus, hero.child[svFort], field[abValue].value]

#applybonus[Bonus, hero.child[svRef], field[abValue].value]

#applybonus[Bonus, hero.child[svWill], field[abValue].value]

I figured this one out. I had to check "Show in Activated Abilities List". When I read the instructions, I thought this would mean the ability was always on....but this is what has to be checked to make a checkbox and name appear so the ability can be turned on and off.

As soon as I tried checking that, retesting, and then trying a character, it worked perfectly.

thanks for your help!