scrolling wil not mix with panning as the drag event is consumed by the map when occuring on the map so scrolling would only occur when the drag event is outside the map. This king of UI is used in many apps.
Anyway bad UX or not, this doen't answer the question of how to have a native component that is part of a scrollable container (it can be a native map that is purely static (all controls disabled) or just clickable but not pannable or event just any browserwebview displaying some html content). And setting the parent component scrollable or using a layout different from LayeredLayout for the parent shouldn't affect the way the peercomponent is displayed (see the ticket oppened on github for details).
As for the preffered size, I don't apply it to the peercomponet directly but to a wrapping CN1 Container. So I might as well have used a table layout with a screen size percentage, the issue would have been the same (the dimensions of this wrapping component is OK in any cases, this is only the peercomponent it contains that has wrong dimensions and sometimes exceed it and is cropped to its boundaries)