IwantRevenge, I would say that it is perfectly legit to add trees outside the red lines. The rules as stated say absolutely nothing against that, only against moving trees within the purple lines. If I were CalawayPark, I would probably rephrase the section of the rules to ensure it is as clear as possible.
Permission to not use the lake: what are you, retarded? It says the lake must be there. If you somehow managed to Katrina your template, you can just redownload the original template, save your entire track as an element, and insert it into the recently downloaded template. I can't imagine you're that far done with your coaster already that having to do so would be a major pain... just take note of what it was that totally pwned your template and you should be fine. If I had to guess, I'd say it was use of the Construction Kit to Tunnel Test your entry. In that case, save two copies of your track. One to serve as the original, and one on which to conduct the Tunnel Test. That way, when the CK fubars your terrain in the process of tunneling, you're not simultaneously screweded.
Which brings me to Eric's question. Eric, Tunnel Testing is simply a means through which we're able to determine rider clearance over the entire track. Let's say you're riding in a B&M hyper on either of the outer rows, and you have some mental condition that causes you to stick your arms straight out perpendicular to your body when you get excited. If the entire track passes tunnel test, no supports, track parts, or trees are visible from within the tunnel and you should return to the station with all limbs intact. If not, however... FWAPP! Welcome to the Amputee's Club! Same goes for hands straight up: a track which passes tunnel test should allow you to return unharmed, whereas one that does not could effectively (and efficiently) guillotine its riders.
I wonder if the French knew about this?
In order to tunnel test your track, you have two options available to you. The less common is to use the NL editor to highlight each segment and apply the tunneled status to the whole track. This way can get somewhat messy, however, as you're likely to lose catwalks and other specifications. The other, more common, way is to use the Construction Kit's Tunneler feature. This will tunnel the entire track with several clicks of the mouse. As described above, though, this could potentially screw up terrain. I'm fairly certain it also results in the Brake Activation settings resetting. Follow the method wayyy up there, though, and you should be fine.
Sorry if I stepped on anybody's toes by answering these questions, I just felt like helping to preserve Calaway's sanity... or what's left of it.