Ahoy,
You can find the DC Dev ISO here:
http://dchelp.dcemulation.org/downloads/DDEr4.rar
It's a DiscJuggler Image but there are other tools available that can burn/mount it.
Instructions and documentation for general stuff like uploading to DC via serial or LAN are included on the disc (I use a USB serial adapter + Windows VM on my mac) -- familiarize yourself with those and try building some of the samples first.
There are also some additional libs, files and tools (not required) in
http://dchelp.dcemulation.org/downloads/
Once that's installed it should just be a matter of checking out the cubicvr 'current' using something like Tortoise SVN, opening a cygwin bash shell to the cubicvr/dreamcast/ folder and running 'make'.
After that you'll find a single example 'cubicvr/dreamcast/samples/bullet/', The elf image and romdisk can be created by running 'make dist' similar to other builds.
I've been hoping to get some time to add more examples for DC and PSP and bring things up to date but that's been pushed back a few months with all the WebGL and Audio app activity that's been on the go.
On a side note: I could really use a proper DC network adapter if anyone knows where I can still find one.
Cheers,