Debian :: Custom Image Hangs

I'm working on a custom Debian "spin" (one customized for personal/work use). I did this once before with an Ubuntu build, but attempting it with Debian has loaded me with a steady flow of walls (everyone loves debugging!). Despite a variety of approaches, none of my images seem to boot. I've tried the following with both SysV and systemd. the search results I find are vague, at best. I'll attempt to categorize and explain this as intelligently as possible.

A variety of ISOs were tried in Virtualbox, so these are the errors they're yielding; I'm currently down on removable media since I loaned my flash disks to a couple students for their finals, so I can't boot that way until Tuesday. I really hope that the error is something that can be identified regardless of whether or not I'm using a virtual environment.

Method 1: This Guide
This appealed to me the most at first because I run a stripped-the-hell-down version of Ubuntu on my work laptop. (Wheezy/Haswell yielded unfavorable results, and at the time Jessie's SysV compatibility was undesirable, but I'll probably switch back by the end of the week if possible.) I have a feeling that this guide may simply be obsolete, or maybe I'm just neglecting a crucial step. Here's the output: a lovely kernel panic.

Method 2: refractasnapshot
With it properly configured (and with syslinux-utils installed -- head-on-a-stick and fsmithred), I tried two different approaches: the first, I ran it within the chroot environment mentioned above; the second, I created a Virtualbox build and ran it within that. Both yielded the same errors:

For each, I received two complains: about piix_smbus and no valid rapl domains, and the system hangs indefinitely (ie, all night). Following some search results, I blacklisted i2c_piix4 and paevm, then rebuilt the image, and mounted it in VirtualBox. At boot:

Code: Select allEDD: Error 0c00 reading sector 276375
No DEFAULT or UI configuration directive found!
boot: _