Actually, those files have been available for months now... In fact, I think they might've been posted just before DART's financial troubles came to light.
Edit: I never really read through it before (I just skipped to appendix C), but there are some interesting highlights, especially regarding DART's other plans.
"While all of the CBD stations currently can accomodate a 3-car SLRV train, some outlying stations can only accomodate a 2-car SLRV as of September 2009." This is before any of the humps were added at stations, meaning that some stations must have a problem with platform length.
Page 68 shows the initial alignments DART looked at.
Only F1, F2, and F3 connect to the north end of Deep Ellum station.
Alignment D1 would reroute the Red and Blue Lines as a north-south route through downtown!
The West Dallas Corridor is identified as "West Dallas to Plano" and has the color pink.
The Southport Line is shown as a separate brown line running alongside the Blue Line only as far north as 8th & Corinth Station.
The humps added to the outlying stations for level boarding are only an interim solution.
The service headways for all light rail lines, including the West Dallas Line and the Southport Line, are given as 10 at-peak, 20 off-peak. Orange Line service is split beyond Pearl with 20/20 to Scyene and 20/-- to Parker Road. TRE, A-train, Cotton Belt, and SW2NE service is given as 20/60.
The Southport Line is reaffirmed as terminating at 8th & Corinth Station.
The West Dallas Line is listed as ending at Victory Station. However, this page discusses the "no-build" option for the D2 alignment.
There are plans to double-track the entire TRE Line, even the Tarrant County section.
DART intends to interline NCTCOG's McKinney corridor with the existing Red Line.
NCTCOG's Frisco corridor would use existing TRE tracks to connect to Union Station.
If the D2 alignment were built, the West Dallas Line would, instead of terminating at Victory Station, run through the existing Bryan/Pacific transit mall to Lawnview Station. Thus, it would serve Deep Ellum Station all day without using it as a switchback.
If the D2 alignment were built, the Southport Line would, instead of terminating at 8th & Corinth Station, run through the existing transit mall to LBJ/Central Station off-peak and Parker Road Station during peak times.
The Cotton Belt is given similar weekend headways to the light rail lines, but this may be a typo.
That's all I've found so far.