Haiku screen resolution

I've used Haiku on several computers but lately I've largely used a Dell Desktop Dimension E520 (nVidia GeForce 7300 LS graphics) with an Acer X223HQ monitor capable of 1920x1080 screen resolution.
However, with Haiku R1A2 and several nightlies that I tried since the release of R1A2, I could never get a resolution higher than 1650x1050 (using a Haiku nVidia TNT/GF driver from Haikuware -- and yes, I did try all of the available nVidia drivers in Haikuware).
Then, a few days ago I tried another nightly (haiku-nightly-r39742-x86gcc2hybrid-anyboot) which when installed on a 2.9 GB partition on the same machine gave a 1920x1080 resolution without any work on my part.
Great! Now Haiku looks even better than before.
But, aren't nightlies somewhat unstable? How can I get the new graphics driver into my version of R1A2 which is stable (even though it's an Alpha)?
Well, I tried various things such as:
1. Using a usb key with the r39742 nightly installed and copying the /boot/system folder from the nightly to Haiku R1A2 (I first renamed the existing system folder).
2. Copied /boot/system/add-ons/kernel/drivers/bin/nvidia, /boot/system/add-ons/kernel/drivers/dev/graphics/nvidia and /boot/system/add-ons/accelerants/nvidia.accelerant to the same folders in R1A2.
Result? No change in resolution. Indeed, R1A2 seemed to be messed up as a result of my experimentation such that Web+ no longer worked, the mail-daemon seemed to be in trouble and the python SimpleHTTPServer no longer worked.
So, I had to do a clean reinstall.
I also posted to the Haiku forum on this issue but so far, no answer found.