The other thing you might want to consider doing is to increase the base amount of memory allocted to Java.
By default, Java sets itself up and only allocates a very limited amount of memory (100mb from memory) which is often not enough to handle numerous windows being opened at the same time. You can increase the amount of memory and this usually solves a range of problems that otherwise keep occuring.
You need to change the memory setting in the Java section of Control panel and while I can probably try to explain how to do it, you might be better calling the Commsec help desk and they will send you an email with the steps necessary for your particular OS.
