Stew
There are no such things as 2.0 overlays.
There is a VASL overlays extension, current version on VASL.info is v2.04. It contains the latest draggable overlays, adding to those in previous versions and maybe changing some from previous versions (bug fixes).
In order for these overlays to show properly for all players in a game, they should all be using the same version of the overlays extension. That is the most likely problem and the first thing to check (hard to do when you are spectating I know).
Also, overlays can come from the overlays extension or from the "traditional" method: the Overlays button on the Boardpicker wizard used when selecting maps, making terrain transforms, etc. If some players are using one method of sourcing overlays while others use the other method, then you will get the issue you witnessed. Some will see the overlays and some won't.
If you can give me scenario details, I will do a more in-depth check, but I suspect one of the above 2 problems is the cause.
Doug
PS. This is why auto-syncing of mapboards is such an awesome addition to VASL - never have to worry about this stuff with boards*.
* Unless of course your board directory is not set properly and then shit happens.