Hi,
Example for each actions would be good of course, tho I think it would only go so far as the particular use in that possible example, an action in itself is not much doing anything in terms of feature in your game, it's the usage and context that make sense in the end, so it is indeed difficult if you don't have a clear understand of what Fsm can do for you to find the right action to use.
It's like asking Unity to provide an example of each api functions... it's not really helping finding the right function, because you woul dend up with 1000's of example and going through them would not be very effective.
I suggest you go over all the samples provided by playmaker, and also watch the videos and screencasts, this way you can pick up design patterns and then really nail what action you need specifically, find out if it's thre or not, and don't hesitate to ask us on this forum, Most of time, after two or three searches you will start to be a lot more autonomous with finding the right action.
now: The second options ( all of them actually) is really completely doable in Fsm, you can destroy gameObjects with playmaker, search "destroy" in the actions browser search field ( search in the action browser window this is the best way currently to find out what's available for a given purpose).
The biggest hurdle in a worfklow where scripts and Fsm are working together is to find the right balance between what should be done in playmaker and what should be scripted. On top of that, both system will want to communicate: I am always using a combination of Fsm and scripts instead of trying to make everything in playmaker and create custom actions just for that projects, I prefer having my scripts using the playmaker api to access fsm, sent events, or ser variable from scripts rather than writing a custom action that tight to one of my script. I don't think this is a good idea in many cases, unless that script is a "framework". Custom Actions "need" to be reusable in any projects, this is of course just my opinion, and it's perfectly acceptable ( and faster many times) to write a custom action to bind playmaker and scripts together.
so try to delete and create prefabs with playmaker, if you have trouble, don't hesitate to ask here, I'll be happy to provide working example if that helps you moving forward.
Bye,
Jean