Tulwar stamped blade mark question

[Matt Easton]

Hi folks,
I come across quite a lot of tulwars here in the UK and many of them have blade markings which I would like to understand a bit more about.

For example, some better quality blades seem to have a sort of stamped design or maker's mark in the forte of the blade, often under one of the langets - is there somewhere I could learn more about these? Are any by known makers or centres of manufacture?

Secondly, some blades have engraved crosses or other marks on them, which some people claim are 'kill' scores - is there any truth to this?

Lastly, what do you make of these stamps attached? They seem to be like a cross between the stamped makers' marks and the incised crosses you sometimes see.

Thanks,
Matt