Thanks for the compliments, guys! To answer a couple of questions, Filasimo, well, that could be done, but apparently the traffic signals are very finicky beasts. I've talked with Jan (Swamper77) about it, and he may be helping out.
And Matt (threestooges), to answer your questions, I am planning on squeezing down the center lane a little bit and adding a narrow sidewalk to the edges. Right now that texture is basically lifted directly from the center tile of the TLA-7. The TLR-3 is indeed an addition to the Roads, and does not replace them. Basically, the way the TLR-3 works is that you place a "starter" puzzle piece, and drag a normal Road out of it. Due to some additional coding added into the puzzle piece, it actually converts the Road being drawn out of it into the TLR-3.
That's the same principle used for the Draggable GLR (starter puzzle piece -> drag Elevated Light Rail out of it), which does indeed exist and will be released as part of the next NAM, which is coming out very soon.

Basically, with that technology and the override technology used for the RHW, OWR-5 and the other TLAs, it's possible to extend the existing networks almost infinitely, such that you can get them to act as if they are completely new networks.
And yes, Steve (Zaphod), it can be done with pretty much whatever network.

Hope that answers your questions. Thanks again for the feedback--I really appreciate it, and I'll be back with more soon.

-Alex