SharePoint 2010 - Fast Search Disk Space Problem

The organization I work for uses Fast Search and the drive where the search index is being stored was running low on disk space. I thought it was the index itself that was growing but as it turned out my problem was being caused by click-through. The folder, "...data\sprel\worker\build_proc", was being filled with files. I used the "spreladmin" utilty to stop the process and deleted the files. So far I have not been able to figure out what is causing the problem and since, in our case, there isn't much of a benefit in using click-through I just decided to leave the service off. I did discover some nice command-line tools for working with Fast Search Server. You can find them here.