Here's the log, with the important stuff bolded. My rsvars.bat is where my XE5 is installed, on a completely different drive and path (e:\rs\bin\rsvars.bat).
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************************** INITIALIZING SETUP FOR TMS Scripter v6.2: 08-10-2013 11:14:16 ***********************
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<snip>
**********>> Delphi XE5 <<**********
Successfully copied file d:\src\tms\TMS Scripter\source\packages\xe5\tmsscripter_xe5.dpk to d:\src\tms\TMS Scripter\source\packages\xe5\Copy of tmsscripter_xe5.dpk
Checking dependencies of tmsscripter_xe5 in Delphi XE5.
Adjusting package dependencies. 25, 1
Starting compiling of d:\src\tms\TMS Scripter\source\packages\xe5\tmsscripter_xe5.dproj in Delphi XE5.
Finding Root Path for Delphi Version 25
Root Path not found. Using default root dir
PACKAGE : d:\src\tms\TMS Scripter\source\packages\xe5\tmsscripter_xe5.dproj
COMPILE PATH : C:\Users\sean\AppData\Local\Temp\is-4SMGV.tmp\tmsbuild.bat
COMPILE PARAMETERS: "C:\Program Files (x86)\Embarcadero\RAD Studio\12.0\bin\rsvars.bat" "d:\src\tms\TMS Scripter\source\packages\xe5\tmsscripter_xe5.dproj" "/target:Build" "/p:config=Debug" "/p:Platform=Win32"
BUILD FAILED!
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