Well, I tried soldering the pomodoro timer from the underside, and, essentially, my skills were lacking – though I suspect I also tried to do something you just shouldn’t really do. You see, I was going to attempt to solder wires directly from a point on the underside to another point. The problem I run into is that I can’t really add a wire on top of a solder point like that. Have a gander at the image below to see some of what happened.

The first thing that went rather wrong was when I was trying to solder an ISP header on the perfboard. I’m talking about those three missing islands at the bottom center of that perfboard. I noticed, after soldering, that what I had soldered was skewed and wouldn’t hold my connector. So, I tried to bend it a little so that it would stick – big mistake there. What I ended up doing was tearing the copper islands off the perfboard, rendering that connector pretty much useless.
The second big problem is right in the middle of the photo. You can see some sloppy soldering there, and what looks to be a loose bit of metal in the middle of that solder. I was attempting to make a nice bridge between the central rail and a pin using a tin wire. However, by trying to put it on top of an already soldered pin, I ended up just trying to smush it next to it, which quickly became very messy. In part, I think my tin wire is too thick. If it were a little thinner, I could have it wrap around the pin and then solder the two together. Secondly, I tried to do this the wrong way around: I first soldered the pin, and then tried to lay out the wire. As a result, it started shifting. I think I need to solder the other end down first, and then either wrap the other end around the island awaiting the pin for the final soldering, or wrap it tightly around the soldered pin and try to melt that in.
The top part is something I’m more pleased with, despite the top right being a little messy. I should have planned this better and laid out the rail first, but either way, I decided to put a single ground rail there to connect all the LEDs to. Sloppy as it is, I think it would have made a really stable connection.
Overall, I think I need to conclude two things: firstly, in trying to make these connections work out, I ended up using far too much solder in places, causing these unsightly bumps. Secondly, I tried to be a little to flexible in this process at this point, which didn’t work out at all. What I need to do is plan out the perfboard in far more detail before starting to solder. Perhaps I’ll put it all on a much larger space. Alternatively, maybe I’ll add another dimension to it by using two bits of perfboard and a connection between them – if I screw them together it’ll be someting of an open box, as it were. That would certainly give me some more space.
Either way, this failure gives me a great opportunity to redesign and improve what I have here. I’m looking forward to making this thing work after all.