How do I work on larger collections without running our of memory ?
The start batch files and sh files for RcTools have a setting for your Java maximum memory. You can make this larger for your collections by adjusting the -Xmx setting. The default is -Xmx512m for 512 megabytes of memory. If your tool reports an out of memory error you can increase this setting to available memory in the machine less start up. So a machine with 2 gigabytes of ram could easily be set to -Xmx1024m for this setting.
You can find the batch files under your installation directory. For Windows the default location is C:\Program Files\RcTools\bin\ and on Mac OSx installs the default is the /Applications/RcTools/bin directory.