[[:Category:Context labels]]
It's used the same way as it was before. The only difference is that you can't use the label templates alone, like just {{US|archaic|military}}. You have to put {{context}} in front for it to work. You can also use {{cx}} which is a shorthand. {{label}} is another alternative which takes the language code as its first parameter, instead of as lang=.
What has changed is the way the label data itself is stored and processed. When you want to create a new "recognised" label, you don't create a template, you add an entry for it in Module:labels/data instead.
That helps. Sorry I have been hard at work reading the Wiktionary:Beer_parlour#No_more_Mr_Bad_Guy soap opera. Can I ask another off-the wall question. Is SemperBlotto really gone? and is that the only repercussion from that whole "fiasco".