So i dropped down the Well and according to a walkthrough i found i'm supposed to open a grate. I found the grate, and i also have the key that the walkthrough mentioned, but i can't open the grate with it.
I tried using it on the crate a lot, it won't open.
According to the walkthrough the only other key is actually behind the grate somewhere.
Is there any special magic key/interface combo that i have to use ? The game sure has a horrible UI, even for the standards of the time.

Turns out i had to find an incredibly hard to see key in one of the well rooms. Ugh.