I also have some problem with installing Spads. I compiled spring and spring-dedicated from the git source. spring and spring-dedicated are located at /usr/local/bin/spring and the game by default is installed at /usr/local/share/games/spring
Then I ran the SpadsInstaller from my home directory and here is what I get:
1/12 - Which SPADS release do you want to install (stable,testing,unstable,contrib) [testing] ? stable
NOTICE - [SpadsInstaller] Components are up to date, proceeding with installation...
2/12 - Please enter the absolute path of the unitsync library (libunitsync.so)  ? /usr/local/lib/libunitsync.so
NOTICE - [SpadsInstaller] Generating Perl Unitsync interface module
3/12 - Please enter the absolute path of the spring dedicated server (spring-dedicated)  ? /usr/local/bin/
3/12 - Please enter the absolute path of the spring dedicated server (spring-dedicated)  ? /usr/local/bin/spring-dedicated
4/12 - Please enter the absolute path of the spring data directory (for maps, mods...)  ? /usr/local/share/games/spring/
NOTICE - [SpadsInstaller] Checking Perl Unitsync interface module
ERROR - [SpadsInstaller] Unable to load Perl Unitsync interface module (Can't load './PerlUnitSync.so' for module PerlUnitSync: /usr/local/lib/libunitsync.so: undefined symbol: archiveScanner at /usr/lib/perl/5.10/DynaLoader.pm line 192, <STDIN> line 5.
at PerlUnitSync.pm line 11
Compilation failed in require at (eval 10) line 2, <STDIN> line 5.
BEGIN failed--compilation aborted at (eval 10) line 2, <STDIN> line 5.
All this under Debian Squeeze 32bit