Unable to build a *.flatpak for this project

[HopperMCS]

@alexlarsson, I'm having Flatpak troubles (I'm in Fedora 24):

I don't know where else to put this, and it seems you're the guy I should ask.

This is a project I've been working on to learn how different parts of a GNU/Linux system come together with each program. In this case, a Gtk+ application with a CLI backend, GNU Autotools, the works.

So, I've tried thus far to get this repository to build locally using flatpak build, but it gets through the process and then subsequently gives me:

Failed to register: 
GDBus.Error:org.freedesktop.DBus.Error.ServiceUnknown: 
org.freedesktop.DBus.Error.ServiceUnknown

I'm new to this, but the idea of each application (at least partially) being enclosed in its own OS-like environment is really cool. The output is in a shell script:

flatpak build-init logo-generator3 org.christoffen.Logogenerator3 org.gnome.Sdk org.gnome.Platform 3.20
cd logo-generator-2.0.4
flatpak build ../logo-generator3 ./configure --prefix=/app
flatpak build ../logo-generator3 make
flatpak build ../logo-generator3 make install
cd ..
flatpak build-finish logo-generator3 --command=logogenerator
flatpak build-export repo logo-generator3
flatpak --user remote-add --no-gpg-verify --if-not-exists logo-generator3-repo repo
flatpak --user install logo-generator3-repo org.christoffen.Logogenerator3
flatpak run org.christoffen.Logogenerator3

And I've outputted the results to a file and copied them here for further convenience (because I know that without exact output it may be difficult to help):

checking for a BSD-compatible install... /usr/bin/install -c
checking whether build environment is sane... yes
checking for a thread-safe mkdir -p... /usr/bin/mkdir -p
checking for gawk... gawk
checking whether make sets $(MAKE)... yes
checking whether make supports nested variables... yes
checking for pkg-config... /usr/bin/pkg-config
checking pkg-config is at least version 0.9.0... yes
checking for CAIRO... yes
checking for GTK3... yes
checking for gcc... gcc
checking whether the C compiler works... yes
checking for C compiler default output file name... a.out
checking for suffix of executables... 
checking whether we are cross compiling... no
checking for suffix of object files... o
checking whether we are using the GNU C compiler... yes
checking whether gcc accepts -g... yes
checking for gcc option to accept ISO C89... none needed
checking whether gcc understands -c and -o together... yes
checking for style of include used by make... GNU
checking dependency style of gcc... gcc3
checking that generated files are newer than configure... done
configure: creating ./config.status
config.status: creating Makefile
config.status: creating src/Makefile
config.status: creating config.h
config.status: config.h is unchanged
config.status: executing depfiles commands
make  all-recursive
make[1]: Entering directory '/home/mgagemorgan/flatpak/logo-generator-2.0.4'
Making all in src
make[2]: Entering directory '/home/mgagemorgan/flatpak/logo-generator-2.0.4/src'
make[2]: Nothing to be done for 'all'.
make[2]: Leaving directory '/home/mgagemorgan/flatpak/logo-generator-2.0.4/src'
make[2]: Entering directory '/home/mgagemorgan/flatpak/logo-generator-2.0.4'
make[2]: Leaving directory '/home/mgagemorgan/flatpak/logo-generator-2.0.4'
make[1]: Leaving directory '/home/mgagemorgan/flatpak/logo-generator-2.0.4'
Making install in src
make[1]: Entering directory '/home/mgagemorgan/flatpak/logo-generator-2.0.4/src'
make[2]: Entering directory '/home/mgagemorgan/flatpak/logo-generator-2.0.4/src'
 /usr/bin/mkdir -p '/app/bin'
  /usr/bin/install -c ../logogenerator '/app/bin'
make[2]: Nothing to be done for 'install-data-am'.
make[2]: Leaving directory '/home/mgagemorgan/flatpak/logo-generator-2.0.4/src'
make[1]: Leaving directory '/home/mgagemorgan/flatpak/logo-generator-2.0.4/src'
make[1]: Entering directory '/home/mgagemorgan/flatpak/logo-generator-2.0.4'
make[2]: Entering directory '/home/mgagemorgan/flatpak/logo-generator-2.0.4'
make[2]: Nothing to be done for 'install-exec-am'.
make[2]: Nothing to be done for 'install-data-am'.
make[2]: Leaving directory '/home/mgagemorgan/flatpak/logo-generator-2.0.4'
make[1]: Leaving directory '/home/mgagemorgan/flatpak/logo-generator-2.0.4'
Please review the exported files and the metadata
Commit: c585870711450e45f0b6c19aefee27ab11d9729d84ea06fee81a99d295c2fe03
Metadata Total: 9
Metadata Written: 2
Content Total: 2
Content Written: 1
Content Bytes Written: 167 (167 bytes)

Also, I have an image of the terminal's error after I ran the script:

And I'll also include the direct files (specifically, the script and the results):

build.sh
build.sh.txt
(rename and take off the .txt to turn back to shell)

results.txt
results.txt

Sorry if I'm wasting your time. It's not easy to maintain something that has spiked like Flatpak, I'm sure.

Thanks in advance for your help.
--MGage Morgan