To ensure the best soaking in without clumping I prefer to tale a hole other spray bottle filled with water and dish soap and completely soak the balast then go in with the eye dropper

I did this conversion about a month ago and the hardest part was isolating everything and rewiring the whole thing. Robert pretty much summed up everything and I did mine the exact same way.

Ok well the more connections or (feeders) you install the better more consitant power you will have. This is easy just run a main set of feeders under the layout and every 4-6 feet of track run a feeder up to the tracks. Color coding the wires will insure you do it all correctly with no shorts. Next, these switches how old are they and what condition, I wouldn't expect a new turnout to always derail things but an older one might have been used long enough and is starting to misalign. Check that the points on the turnout line up nicely with the outer tracks. Maybe watch as a train rolls over it and try to pin point the trouble spot on the turnout. I don't know what that's about but the frog is the flatend like x part where the rails cross on the turnout and it cannot and should not be removed because the is no reason to. Finally I agree with whomever told you to get better turnout machines bucause when using  regular non road bed track the spring like ones are pretty much impossible to get working well but the ez track ones should work alright for now. The constant pressure switch machines like the tortise by circuitron are very good machines which include many great possibilties for signaling are also quite expensive so unless you are prepared to spend loads of cash on these the eztrack machines should work fine. So hopefully I've covered all your questions and good luck!
Tyler

DC and DCC  use the same track but you may have seen the DCC switches which have a decoder Inside to swich the switch.

Proto 2000 has lighted cabooses, no marker lights. There is a lights and flasher kit by jay-bee for athearn cabooses and probably fit in a bachmann somehow. Here's the exciting one though, rapido Is designing an amazing caboose with marker lights and interior lighting along with so many other details, what I think might just be the best HO rtr caboose out there. I can't wait till fall when it suppsedly comes out

I own one of these, and I agree it is a very nice model. I just wish there was more room for a decoder without taking up the cab. So mine is still on display until I find a small enough decoder

Yeah they are, they recently came out with a very nice ps2-cd high side covered hopper kit. I had to get a few

The truck bottoms should have a clip on either end so just carefully pop itoff at the clips. If it was an athearn blue box that I'm not suprised it's 10 years old because athearn has been around for years and most of the blue box locomotives are just floating around even though not in production.

Your right about the wheels not supposed to be free rolling, athearns are all wheel drives. It might be something with the gears. You should be able to pop the underside of the trucks or at least one off to view the gears. Stripped gears is the only thing I can think of fitting your description

Wood land sceinics is very good qualy at an ok price. Preiser also makes very nice figures along with many animals and over all a way bigger variety as seen in the walthers reference book. I agree that the life like figures and other cheaper ones are good for passenger cars and buildings, places that aren't directly viewed for their detail but more as just people. I find the life like figures are a bit shiny compared to woodland sceinics figures so a light dull cote really helps, and mabye even a grimy wash to bring out the wrinkles and stuff

I also had that problem with my first layout, and after getting annoyed not being able to run my rapidly increasing number of modern equippment I had taken a rather harse saw to the obstructions, mainly tunnel portals. That was one of my great mistakes, along with tight curves that my new layout has done without. I figure as long as a overheight double stack and my auto-max's clear I should be good.

Some locomotives and brands whine less than others, my brand new kato being tested on DC sounded like it had a decoder because there was close To whine. But other locomotives can whine as loud as a full volume sound decoder. So I'm not sure what does this variation, maybe the motor or something in the wiring but there must be some way to quieten a dc locomotive. A very small muffler:)

If it is a short you should see some disturbance on the controller, even a flicker. I only know of that happening with relatively short wheelbases stalling over #6 and 8 switches. Check the power throughout the switch there could be a dead rail in it.

Wow, that is one big decoder

Sounds like you've planned the layout out VERY well and it sounds like lots of fun.
Good luck
Oh DC or DCC