Ok, to clarify my progress, I've got to the point where I used the initial machine in the workshop to fix the key (weld) Which opens a door in the first corridor.  As soon as I go into that room I'm attacked by a flying creature, at which I trap in the room by getting out and closing the door.  Thing is, I'm no where the wiser because I've found nothing in that room of value except for the dynamite on the table and a couple of items on the other desk draws.  So, what is in this room to make it worth while to fix a key for, that has nothing of value in it?  At this point, I'm stuck because it appears that I've achieved all the tasks, except to open the coded door at the end of that same corridor that the door was used with the key.  And I can't find the card key used to open the second door at the bottom of the stairs.

Do not interpret this query as a negative issue though, this is an excellent and challenging game, and is an inspiration to the genre

[EDIT] Forgive me, found the walkthrough in the FAQ.

Paul.

I can't believe this right... I've completed the game now, but what got me stuck, was the room with the broom and the smelly powder. It never occurred to me that the door to this room, Opens outward!! I had made the assumption that doors were pushed. There's me trying to push the door and nothing happens. I look everywhere to see if there's a way in. Anyway, at long last.. I pulled the handle in frustration, low and behold!!

Slaps self. Anyway, an enjoyable experience, and I look forward to seeing more.

Paul.