You have (at least) 2 issues - the complexity of the environment (the server) and the complexity of the GUI.
There are many tools for automating GUI testing. All of them are more or less fragile and require pretty much constant maintenance in the face of changing layout. There is benefit to be gained from using them, but it's a long term benefit.
The environment, on the other hand, is an area that can be tamed. If your application is architected using the Dependency Injection/Inversion technique (where you 'inject' the server component into the application), then you can use a 'mock' of the relevant server interfaces to enable you to script test cases.
Combining these two techniques will allow you to automate GUI testing.
One final thought - good luck!