We're currently testing 7.4 and we've come across an error on self service when opening a new request and selecting a raise user.
When the user's name is entered the following error is displayed at the top of the window - which seems to prevent any further progress:
Type mismatch when attempting to set attribute value _CatalogueHierarchy
I'm not sure if it's anything to do with the service catalogue or not - although this appears simply when locating a raise user from the drop-down field (on our generic OOTB request process) before any other fields have even been filled in.
This could well be due to something we haven't configured yet (for all I know) but any advice and suggestions appreciated.