I'll second this. I loaded it into an existing game and it kept popping up notifications. I only had about 20 things with updated productivity but it kept popping up a full text box of notifications every 5 seconds or so and never stopped. I did use non-default settings, 1000 crafts for 0.001x productivity. I noticed in the file that some internal rounding is probably to blame.
As a workaround, you can edit out/comment line 88 of utility/product_cache.lua
