1. Game crashes when using only space age and your mods, doesn't crash if either bzcarbon or bzsilicon is included

Failed to load mods: quirkycat_ores/data.lua:41: attempt to index field 'calcite' (a nil value)
stack traceback:
quirkycat_ores/data.lua:41: in main chunk

1. Also error messages are different depending on which one of them is used by itself

bzlead:
Failed to load mods: Error in assignID: item with name 'tin-ore' does not exist.

Source: lead-ore (resource).

bztin:
Failed to load mods: Error in assignID: item with name 'lead-ore' does not exist.

Source: tin-ore (resource).

bzzirconium:
Failed to load mods: quirkycat_machines/data-updates.lua:23: attempt to index field 'steel-basic' (a nil value)
stack traceback:
quirkycat_machines/data-updates.lua:23: in main chunk

Hope all that helps with your work

Thanks, excellent diagnostics, makes fixing much easier.
Should all be fixed in the next update.