I just tried the starfield with both 1920x1080 (HDMI) and 1280x1024 (DVI), and it works perfectly fine,
VSYNC and Ctrl-C included.
Could you do me a favor and try this with basicengine-firmware-h3-v0.89-167-g730c.zip as well as with a current build and see if there is any difference?
I have recently changed the LCD interrupt to use vblank instead of the scan line trigger because that gives more time for rendering the next frame. I have no idea why Charlie used the scan line instead of vblank; who knows, maybe there is something broken with it.
That said, in Engine BASIC pretty much everything is timed off the LCD controller interrupt, and if there were a problem with it, it would break the entire system, not just a few select features...
[BTW, the reset button stopped working for me all of a sudden because the system failed to boot off the SD card after a reset. It worked perfectly fine just days ago, with the same SD cards and the same board. Anyway, updating the SPL to v2017.05 fixed it for me, and I have therefore pushed a new SPL binary to the allwinner-bare-metal repository. There won't be a nightly build until I commit some change to the basicengine-firmware repo, though.]