I've just updated to the latest version of RoboHelp 2019, and managed to import projects by deleting the XPJ and CPD (or they won't import...).
But now my project has lost all it's variables. this isn't an issue for this particular project, but one of our larger projects has multiple flavours of help, with a complex and lengthy series of variables, probably 200 or so.
So it's back to waiting for update #2? The stupid thing is I like the new version of RH, it seems intuitive to use. But I can't upgrade until they find a way to deal with the existing functionality, or I'm going to waste time I don't have recreating something that already works.