Just to be sure.
you did the following:
1. Placed the snowbox entity in center of the player marker.
2. You added the snowbox_followplr.lua to the snowbox entity.
3. You placed a trigger zone and shaped it to the seize of the inside of the building
4. You added the snowbox_indoor.lua to the trigger zone
and it's still not turning off...
I'll have to have a look tonight when I get home, haven't got GG installed at work, I'll see what I can come up with, but I think it may be something has changed with GG. It was definitely working in 1.12 (albeit invisible until you changed the transparency setting in its fpe) though.
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