Crash log: https://paste.ee/p/gq4b7

Profile: https://paste.ee/p/CuAYp

[13:06:33] [Server thread/ERROR] [lostcities]: Chunk profile: hextechrare
[13:06:33] [Server thread/ERROR] [lostcities]: Is City: true
[13:06:33] [Server thread/ERROR] [lostcities]: Building type: shopping_open00
[13:06:33] [Server thread/ERROR] [lostcities]: City level: 0
[13:06:33] [Server thread/ERROR] [lostcities]: City ground level: 71
[13:06:33] [Server thread/ERROR] [lostcities]: Num floors: 4
[13:06:33] [Server thread/ERROR] [lostcities]: Num cellars: 1
[13:06:33] [Server thread/ERROR] [minecraft/MinecraftServer]: Encountered an unexpected exception
net.minecraft.util.ReportedException: Exception generating new chunk

Profile is a mix of rare and realistic. No special assets. Tuning for massive, very rare cities. Major changes I have made outside of blending the profiles are:

S:cityChance=0.0005
I:cityMaxRadius=1024
I:cityMinRadius=768

Other tweaks are minor adjustments within the profile and biome exclusions (mountains).

Is it possible that this is an issue when I:buildingMinCellars=1 (or is set >0?) and the building being generated doesn't have a cellar level?

I was able to get around the issue in two different seeds with the above NPE being caused generating shopping_open00 on one and shopping_open10 in another world by setting I:buildingMinCellars=0. Once that was done I could load either world and continue just fine.