I've finally figured out that it looks like "usage" was replaced with "trigger" and that accessing variables needs to be done with "@(name)" instead of "@name", but I'm still unable to translate the example given for a typewriter into something that actually functions. Also saw nothing to indicate to me that you have to have a vessel in your inventory to cast it. It'd also be nice to be able to cast using a trigger of a carried vessel, or to be able to use those triggers as an implicit cast.
Additionally, nothing told me I could use "learn to" to look at help for actions. I found this by mistake. And "learn to cast" shows the instructions for "drop" (or was it "take" I forgot, either way, it's wrong!)