Hi @yadamz,
I just fired up a new Ref App 2.6.0 with VDUI 1.3 and everything works fine. Do you realise that documents can only be added to a visit? Where you by any chance looking at a patient outside a visit? This will likely be relaxed in VDUI 1.4, see this thread.
What Flash error did you get exactly, this?
Webcam.js Error: Adobe Flash Player not found. Please install from get.adobe.com/flashplayer and try again.
Also this should not happen if you use Chrome, where you using Chrome?