Since I couldn't get dsss to work on paths that had spaces (and knowing that dmd won't work there either), I tried using subst. In short, what I have is my root dsss directory (where bin et al. reside) mapped to the drive Q. dsss net install dmd works, but dsss net install tango doesn't:
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tangocore
tango
Command: cd tango
Command: q:\bin\dsss.exe build
+ q:\bin\dsss.exe build
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tango\core => DO-tango-core
tango\io => DO-tango-io
tango\math => DO-tango-math
tango\net => DO-tango-net
tango\stdc => DO-tango-stdc
tango\sys => DO-tango-sys
tango\text => DO-tango-text
tango\text\locale => DO-tango-text-locale
tango\util => DO-tango-util
Installing tangocore
Installing tango
Command: cd tango
Command: q:\bin\dsss.exe install --prefix=q:
+ q:\bin\dsss.exe install --prefix=q:
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Installing DO-tango-core
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+ making directory q:\tmp\DSSS_tango\tango\tango\q:\include\d\tango\core
Error: q:\tmp\DSSS_tango\tango\tango\q:: The filename, directory name, or volume label syntax is incorrect.
Command q:\bin\dsss.exe returned with code 1, aborting.
Error: Command failed, aborting.
This is with dsss 0.73 on Windows XP.