Install Error unpacking JAR files

From what we've been able to see, this could be a really great app. However, we're having problems getting it to install completely. We get to the "Unpacking JAR files" part of the install, which takes quite a long time, but it eventually fails with a critical error that backs out of the install and uninstalls everything.

However, being that we're used to Windows apps that don't install themselves correctly, we noticed that if we kill the install process when the error comes up then the uninstall doesn't occur and we can run the program. BUT, of course, it seems that some things are missing. For one, we don't have IN and OUT statistics for our interfaces, only IN. We were missing conversation data for a while, but a few reinstall attempts seem to have fixed that. It seems that if we could just get the install to finish without the JAR unpacking failing, we'd be good to go.

Any thoughts?

The installer that we're using is:
AdventNet_ManageEngine_NetFlowAnalyzer_4_windows.exe
We just downloaded it earlier this evening.

The exact error that we get is during the stage that says "Unpacking Jar Files. This will take a few minutes. Please wait ...". The title of the error dialog is "Severe", and the message is simply "Error While Unpacking". The dialog belongs to the "IKernel.exe" process.

-R