Getting Latest Updates to work in MAF

We've been trying to implement Latest Updates for WLUK in MAF. We've done all the config (and I've compared what we've got with CPW and it looks OK) but for some reason the DataSourceContainer in the NovusInPlanDataSourceService is empty when it comes to looking up the datasource we want updates from (it's not empty when looking up anything else!) We are successfully searching and retrieving documents from the collection set, but at that point it's using the collection name rather than the collection set. The wiki documentation says we're meant to provide the name of the collection set (which is what we're doing, and what CPW does) but why can't it be found?