The -trace switch is only useful in troubleshooting situations. It causes an enormous amount of information to be written to the log file (ashlog.log) which can help in debugging difficult problems.
Note that although the normal location for the ashlog.log file is in the same directory as the miame.ini (or in the directory specified by the LOGDIR= statement in the miame.ini), certain trace operations may occur before A-Shell has established either of those locations. For those traces, it uses the TEMP directory to create ashlog.log. This can be particularly useful in debugging problems relating to not being able to access the miame.ini (such as networking problems).
So if A-Shell fails to launch correctly and you can't figure out why, try adding "-trace" to the command line (in the properties of the shortcut) and then look at the copy of ashlog.log that will be found in the TEMP directory for the user. For windows, this is typically: "c:\Documents and Settings\<username>\Local Settings\Temp\ashlog.log"
For UNIX, it will be "/tmp/ashlog.log".
Note that if the launch proceeds to the point where it starts to process the miame.ini file, subsequent log entries will go to the regular ashlog.log file in the directory where the miame.ini is (or as specified by LOGDIR=).