I made a RefAlias that's filled by a horse. I put a script on it that atm is pared down to just this:


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Scriptname hrfHorseCheckScript Extends ReferenceAlias


Event OnActivate(ObjectReference akActionRef)

Debug.Notification("I was activated.")

EndEvent

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I load the game, make sure the horse that fills that refalias is in front of me, and I activate it. Nothing happens (besides mounting the horse). I don't get the "I was activated" message. If I use Debug.Trace it doesn't get written to the log. What am I doing wrong?

I don't see anything wrong with the script. Try adding an OnHit event and testing if that works. If it does, then I guess it's impossible to activate horses... If it doesn't then you must have done something wrong and the horse is not actually filling that alias.

Turns out it works. It just takes a minute for the activation to register. Literally a minute, at least. The hit was registered a little faster so that let me know to try waiting longer for the activate. But not much faster; the OnHit took over 30 seconds. Crazy.

Scripts in Skyrim have a script budget and when that is used-up, nothing happens (script-wise) until that budget is available again.
In short, that means you have some other script(s) running that use-up all the budget time-slices.

It would usually be something that calls RegisterForUpdate with a small interval or a OnHit event not taking into account destruction magic (flames spell, etc.) that spam OnHit events -- minutes into the future.

To pin-point which script(s) are ignorant about this, you can try to enable http://www.creationkit.com/INI_Settings_(Papyrus)#bEnableTrace and then in-game call http://www.creationkit.com/DumpPapyrusStacks and http://www.creationkit.com/DumpPapyrusUpdates from the console. This should give you enough to pin-point a specific script file.
The log-file is stored at \My Games\Skyrim\Logs\Script\Papyrus.0.log; Papyrus.0.log is always the most recent one.

Thanks Xetrill. I watch the Papyrus log for my stuff. I've been ignoring everything else. Guess I better start paying more attention.

Do you know if there's an ini setting to raise the script budget specifically?

I haven't tried changing any of these values, but I think you want to look at fUpdateBudgetMS, iMinMemoryPageSize, and iMaxMemoryPageSize:

http://www.creationkit.com/INI_Settings_%28Papyrus%29

It turns out that while the horse activation event is set off fine by me, and by any random NPC I command to activate it via the console, the one actor I actually care about activating it is a follower and when she does it nothing happens. *laugh/cry moment*