Short version: The All-in-One contains all of both WV1 and WV2 and replaces both. The good news is that last I checked, the authors are doing a fantastic job with the tedious task of keeping both the separated and AIO options fully updated in parallel. That's a big headache that not everyone undertakes, so I wanted to take a second to recognize that.
The bad news, though, is that Designer's Choice requires you have the same PLUGIN as the designer, if I'm not mistaken. If the designer used the AIO, and you're using the separated versions of 1 & 2, you'll get errors in plot selection. Likewise, the reverse.
I don't know that there's currently a solution other than making sure which version the designer used.
-asp
P.S. Caveat to all of the above, I haven't actually played a full play-through in almost a year & a half because of several factors, but have been in-game a bunch building city plans the last few months for the contests.