You can enable more logging by going to the Web.config file and uncommenting out the section on trace listeners:

    <add name="eventLogListener"
    <add name="fileListener"
      initializeData="C:\Program Files\SpiraTest\SpiraTest_Trace.log"/>

You need to uncomment the previous section and specify a real file location that you want the trace log file written to. Then you can change the logging levels themselves by changing:

   <add name="generalSwitch" value="1" />
   <add name="queriesSwitch" value="1" />


   <add name="generalSwitch" value="3" />
   <add name="queriesSwitch" value="3" />