i had no project with corona and big ass renderings yet...
but my vray workflow might work for corona too...
sooo:
1. install backburner: even if you have only one machine!
2. start server, monitor, manager
3. in renderwindow: there is a arrow right next to render button-> submit to networkrenderiing
4. search for the slice option, than try how small the slices have to be until you memory is full or 3d max crashs...
5. mark the option to combine it again or do it manually in gimp or photoshop...
(6. there are serval option you can try out, like the render an overleap, so it will blend it together...
i'm not sure if you have a problem when doing hdcache, maybe you get ugly seams!!
the workaround in vray is to precalculate only the LIGHTCACHE on one maschine, and save it out, than load it in, and than submit it so backburner with the slicing option...
i'm not sure how to do this in corona, maybe no need... i think if you use pt-pt you should be fine, just give it a try with a simple scene.
with this technique i rendered resolutions of 15000x10000 (15 slices exr) (i7 2600k 16gb ram)
on my new machine i have 32gb, but still this is maybe not enough for heavy stuff...
tell me if it worked!
all the best
piripi