I obviously can't speak for the developer, but I do not believe this is something that can be "fixed", and even if the above behavior was implemented in a buggy fashion I doubt anyone but Apple could fix it =)
yep, it's definitely possible: just use [theDrawer openOnEdge:NSMinXEdge] and [theDrawer openOnEdge:NSMaxXEdge] to open it on the left vs. on the right instead of calling the vanilla [theDrawer open].
(quick fix) if you want the drawer to appear at the left side of the window just push the window itself to the opposite side before opening the drawer -- or hide it then show it again.
ciao,
Domenico