Used Wordfast and Trados. Both not free and Windows only. Nothing bad about them I can not say, especially about Trados.
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OmegaT was discouraging, when was the last time she looked. Yes, and Java (to tipriti can't do GUI in Java, well in General not the best choice for the program, working with texts, IMHO).
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Tried to write your software in Python (pygtk interface), built something like a working prototype 5 years ago, but gave up due to time constraints.