Posted here cause it's the first one I saw

Failed to load mods: Error while loading item prototype "enriched-lead (item): Key "stack_size" not found in property tree at ROOT.item.enriched-lead
Modifications: Lead

Mods to be disabled:
bzlead(0.2.1)

Failed to load mods: Error while loading item prototype "enriched-titanium (item): Key "stack_size" not found in property tree at ROOT.item.enriched-titanium
Modifications: Titanium

Mods to be disabled:
bztitanium(0.9.14)

Hm. Thanks for report, but I cannot reproduce. Can you let me know your mod list? Or did you perhaps remove K2 from a game in progress?

Oh! I didn't realize until now there was a "no changes" for K2 stack size. that's gotta be it. Will fix.

Fixed in new version, same for Lead.

Stage 1 testing completed. It loads!

If you'd like I'll do some balance runthroughs to help with that.

I have not had a chance to run through K2 or SE with the updated Silica & Silicon yet, so if you notice any major balance issues I'd appreciate.