The recipe for glass is unavailable when using AAI, Crushing Industry, K2SO, and K2SO Tweaks together.
Examining the "Sand Processing" entry in the tech tree shows that it doesn't unlock anything. Neither does the "Glass Processing" entry.
This is NOT caused by K2SO Tweaks, but it seems like a good place to fix it.

elevated-rails 2.0.69
quality 2.0.69
space-age 2.0.69
aai-industry 0.6.13
crushing-industry 0.4.13
fsdl 0.2.2
flib 0.16.3
Krastorio2-spaced-out 1.4.26
Krastorio2Assets 2.0.3
Krastorio2Inserters 1.1.6
Krastorio2MenuSimulations 2.0.2
multispoil 2.1.2
nulls-k2so-tweaks 1.8.1
PlanetsLib 1.13.6