I see that this is not really active topic, but it’s the only one on this forum that mentions SamplerBox, so I’ll bump it 
It took me by surprise to find SamplerBox preinstalled in the OS and that it’s not mentioned anywhere in the UI. I was using SamplerBox on Raspberry Pi before, so I tried to test it on CPI and it kind of works. After connecting midi controller, I ssh’d to the CPI and tried running python /opt/SamplerBox/samplerbox.py and at first it was working, but after trying it again there was no sound. Turns out that if you cd into the SamplerBox folder and run sudo python setup.py build_ext --inplace each time before running SB the sound will work. But after trying to switch the preset (I added some preset from SB website) the sound disappears again.
I also tried to add it to the menu with .sh file with python /opt/SamplerBox/samplerbox.py in it, but it didn’t really work as after running it I was stuck with “loading” image and no way to cancel it. Is there a way to run something like this from the menu in verbose mode?