Well, it took me a good amount of time, but I managed to beat the UHL challenge (#1). That was a brain buster, but I managed to complete the mission; and also decorate an entire half a sheet of paper, while at it, with notes. Thank goodness I can write small.
Essentially, I had to find a LAN server not easily found through InterNIC or public servers, steal a file from it, then use the IP address I was given (1337 LAN), and hack my way towards the main computer system from that address. After I find the main server, I have to upload the file I took from the other LAN server into it. While at it, I also have to cover my tracks, and believe me, you'll be leaving one hell of a log by the end. If you're not quick enough, it may require multiple trips to clean it out.
Luckily, I managed to succeed, and not get noticed. 3 in-game days later, no notice from Uplink. YAY! I DID IT! Took me up to 3 in-game (and possibly realtime) hours to complete it.
I can't wait to try the other challenges.
EDIT:
Okay, the admin did kick me off the server a couple times, but I wasn't successfully traced over the course of 3 in-game days; which to me equals success.
EDIT EDIT:
Actually, I think it actually took me less, since I was trying to find the target servers, but I got distracted by a sample LAN server I wasn't aware of (found in INIC). That distracted me for a good few minutes.
EDIT EDIT EDIT:
Just decided to play a little more with this custom save, and since it was broke to begin with (money-wise, though it did have decent stuff to begin with) with some half-decent hardware and software, I decided to rob some banks. I completely bankrupt a company, did a money transfer trace job, got the money from that mission, then robbed the transfer account, it's source, and then my client that assigned me the trace job.
Is it normal to cackle like a madman after pulling off such heists? Oh yeah, and my hacker-rating went from class 14 to class 3 in 4 heists. No missions promoted me at all. Stood at the top-ranking spot. No missions available at the start, to all kinds, to none available due to untrustworthiness.
I got as many LAN missions as I can get in short notice.