update, actually the whole scaling modes went wrong after the recent updates, I think there's some kind of a problem with canvas sizing in html, as in resizes the canvas to a slighly larger area than it should, but again ONLY on a mobile, in the preview and in appmobi emulator it seems fine. android nexus one, appmobi export.
here's what's going on:
and here's the capx:
to my knowledge, the white margins should be on all sides, in both portrait (big margins on top and bottom, small on left and right) and landscape (small on all sides) as the project is in landscape and has proportsions similar to the mobile screen.
also shinkan got the dropbox working without installing it, thanks! :)