On Fri, Apr 29, 2016 at 11:24 AM, Mark D. McCurry <mark.d.mccurry@gmail.com> wrote:

Personally I use zyn almost exclusively in a standalone sense, but there
is very clear demand for it in the context of a DAW plugin.
While there might be some standalone synths out there which make use of
multiple windows it seems to be very strongly discouraged to do so in
the context of a plugin.

From Apple's "Optimizing Audio Unit User Experience in Logic Studio"

"For even better user interface integration, custom Audio Unit Views should refrain from using overlay windows and from opening sheets or auxiliary windows other than for file browsing. All user interface elements should be presented inside the root Audio Unit View by laying out its content dynamically and resizing as necessary. The host window listens to size change notifications and will adapt automatically."