Using Ext GWT in a closed environment

[SuperSloMo]

I am working on a research project using data from the VA hospital system. Access to the data is tightly controlled to protect patient privacy, and I can only work with the data by remote login to a computer that is networked to other research machines but has no access to the world wide web. I would like to create a client web application for a web service, and Ext GWT looks like a good toolkit to do it with. Does it have any dependencies to resources that would prevent it from being usable in a closed environment like the one I described? If I downloaded the toolkit, uploaded it one of these research machines via their very special protocol, and installed it there, could I create a web client application to run within that restricted network? If so, are there any special considerations I would need to know about?
Thanks,
Mike

[sven]

Does it have any dependencies to resources that would prevent it from being usable in a closed environment like the one I described?

It has to dependencies to the outside. All files required can be served from your internal network.