The following steps are based on the custom sample files and DKMS modules included 
with the orginal Kickstarter AtomicPi image and assume that all steps are being 
applied to a new install of Lubuntu 18.04 LTS.  The process below has only been tested 
on a new Lubuntu 18.04 LTS install.  The steps should work for any Debian-based 
system (or any flavor of Ubuntu), but may require slight modification.  Please be 
aware that extracting the tar file 'atomicpi-gpio-i2c-spi-xmos.tar' from the root of 
the filesystem as instructed below will overwrite any files of the same name that 
exist in any of the destination directories.  This is not an issue on a fresh install, 
but if you have concerns you should extract the archive file to a temp directory and 
manually transfer the files to their final destinations.

The archive file can be obtained from: 
https://bitbucket.org/radu7/atomicpi/downloads/atomicpi-gpio-i2c-spi-xmos.tar.gz

The document you are now reading is located at:
https://bitbucket.org/radu7/atomicpi/downloads/atomicpi-gpio-i2c-spi-xmos.txt

The process (after you've completed your Lubuntu 18.04 LTS install) from a terminal or SSH session:

sudo apt-get update
sudo apt-get install ssh (If you need remote shell access for a headless system and SFTP/SCP access to copy files via the network.)

sudo apt-get install i2c-tools
sudo apt-get install dkms build-essential make
sudo apt-get install linux-headers-generic (Not typically needed with default Lubuntu 18.04 LTS installs.)

sudo apt-get install python (Install Python 2.7 if you have not already done so in order to run the Python samples.)
sudo apt-get install nodejs (Only needed if you intend to use the .js samples.  If you plan to do nodejs development you may want to install npm along with nodejs)

Transfer the atomicpi-gpio-i2c-spi-xmos.tar.gz to your user home directory.  Then from your user home directory copy (or move) it to the filesystem root:

cd ~
sudo cp ./atomicpi-gpio-i2c-spi-xmos.tar.gz /


cd /
sudo gunzip atomicpi-gpio-i2c-spi-xmos.tar.gz
sudo tar xvf atomicpi-gpio-i2c-spi-xmos.tar
sudo cp /usr/lib/node/atomicpi.js /node_modules  (The gpio-test.js sample program will not function unless the atomicpi.js is accessible.)

cd /usr/src/i2c-gpio-custom-0.1.1/
sudo dkms add i2c-gpio-custom/0.1.1
sudo dkms build i2c-gpio-custom/0.1.1
sudo dkms install i2c-gpio-custom/0.1.1

cd /usr/src/spi-gpio-custom-0.1/
sudo dkms add spi-gpio-custom/0.1
sudo dkms build spi-gpio-custom/0.1
sudo dkms install spi-gpio-custom/0.1

sudo systemctl enable i2c-gpio-custom
sudo systemctl start i2c-gpio-custom

sudo systemctl enable spi-gpio-custom
sudo systemctl start spi-gpio-custom

If your user name is something other than 'atomicpi' then the next four commands will transfer the Desktop document links, documentation 
files and sample programs to your user directory.  Feel free to delete the /home/atomicpi directory after you've copied the files over to your 
own user directory.

cd ~
cp -r /home/atomicpi/Desktop/ ./
cp -r /home/atomicpi/doc/ ./
cp -r /home/atomicpi/samples/ ./

If you want to build the xmos audio firmware please see the README file located in (this document does not detail this process):
/usr/src/xmos-audio-firmware/

Now go ahead and reboot and then test the programs in the 'samples' sub-directory of your user's home directory (use CTRL-C to exit each sample program):

cd ~/samples

sudo node gpio-test.js (will turn on the green LED on the large breakout board)

sudo node bno055-test.js (running display of values of the onboard bno055 sensor)

sudo python gpio-test-off.js (will turn off the green LED on the large breakout board)

sudo python gpio-test-on.js (will turn on the green LED on the large breakout board)

sudo python bno055-test.py (running display of values of the onbard bno055 sensor)

Note:  Attempting to execute the gpio-test.js sample after running the gpio-test*.py samples will produce an error as the python gpio-test*.py samples
do not release/reset the gpio resources when terminated.  This may have been corrected in the latest AtomicPi images, but I have not looked into it any
further.  If I have time to do so I will update this guide and the tar file as needed.  My intention for this document was to assist others with getting
basic functionaly of the GPIO and bno055 sample programs working based on the files/modules/samples included with the Kickstarter version of the AtomicPi.