Basic Setup up for Pixel Mapping of LED Pixel Tape/ pixel Sting

Merry Xmas !! 

Dance and light artist here, self taught lighting here :)

I'm wishing to attempt a light dance installation performance. I'm wishing to control Pixel String LED lights from my Etc nomad setup (1024 channel count) - struggling to get my head around connecting my laptop dongle to pixel tape, allowing pixel mapping. I'm reading about DMX to SPI - does that allow pixel mapping? I have pixel string and power but I think I have bought wrong led controller. 

Please could someone explain to me the basic, cheapest and quickest setup options. 

Unclear for example how this fellow achieved this setup -

Huge huge appreciation for any help ! !