Well, well, well... My mIRC doesn't seem to agree with me.
In my DCC options, I've enabled auto-get + minimize and set it to "trusted users only". Then, I added user levels 2, 3, 4, and 5 to the trusted list.
Then, I added myself to the userlist:
Now, that seems all good to me. But, when I try to send a file, it simply does nothing - as if I wasn't on the trusted list.
I've tried disabling the "trusted users only", and it accepted the file there.