Suggestions for using alternate key-mappings for absent num lock key. My keyboard does not have the num lock.

Schematica doesn't use the numlock key by default (though it does use keys on the number pad). You can change keybindings in the normal controls screen (I think). If you're trying to choose keys that aren't on that, consider maybe [ for load, ] for save, and \ for control (but really, any keybindings will work)

I won't be adding an alternate set, because you can change all key binds yourself in the options, under keybindings. You can remap them to whatever you personally like.