Stick with the framework. It doesn't use threads and is event based? Don't use threads, use events, then. The problem can be solved within the same framework, without adding threads into the mix. Starting a long running sub prevents Tk from servicing other events? Make sure your sub cooperates and yields time slices to Tk.

I'm not saying that it is a bad idea to use Tk within a threaded application, but that it is probably not so good an idea to use threads within Tk, since the framework itself is threads-unaware and probably not programmed in a thread-safe way; so using threads within it requires good understanding of the working of both perl threads and Tk.

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