Error when replacing a Stone Furnace with a Steel Furnace. Fuel being used in Stone Furnace is Processed Fuel.

Main mods: SE + K2

19032.905 Script @Fill4Me/stdlib/event/event.lua:153: Fill4Me/fill4me/fill4me.lua:333: bad argument #1 of 2 to 'pairs' (table expected, got nil)

Same mods, same error, placing a burner inserter, with no fuel in my inventory

I get a different error performing the same action (replacing a stone furnace with a steel one.)

'count' real number expected got string.

I'll look into this this week, busy week sofar.

I believe I have this corrected in 0.12.1. Please let me know if I've missed the case you're referring to, as I think this error from 2 years ago is different (but similar wording) to the recent error report.