Unfortunately, not very sure what happened. The installer failed after creating new partitions. I did try to first set up an encrypted disk, which also failed.
ProblemType: Bug
DistroRelease: Ubuntu 16.04
Package: ubiquity 2.21.63.2
ProcVersionSignature: Ubuntu 4.4.0-31.50-generic 4.4.13
Uname: Linux 4.4.0-31-generic x86_64
ApportVersion: 2.20.1-0ubuntu2.1
Architecture: amd64
CasperVersion: 1.376
Date: Sat Sep 17 22:30:49 2016
InstallCmdLine: file=/cdrom/preseed/lubuntu.seed boot=casper initrd=/casper/initrd.lz quiet splash ---
LiveMediaBuild: Lubuntu 16.04.1 LTS "Xenial Xerus" - Release amd64 (20160720)
ProcEnviron:
PATH=(custom, no user)
LANG=en_US.UTF-8
SHELL=/bin/bash
SourcePackage: ubiquity
UpgradeStatus: No upgrade log present (probably fresh install)
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apport-collect 1624786
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