Thank you for the feedback!
Yes, the software runs only on Windows.We would be interested in porting it over to Linux but that would depend on demand and how mature moonlight is with regards to support for .Net 4. In the meantime you can check out our video on youtube (as I understand, vimeo has issues with Linux support): Explaining Grammatica... (Youtube).
Thank you for the support! Our stress mark 'engine' will be able to figure when the stress needs to be on a different part of the word depending on context. Our engine will analyze the surrounding words to sort out such 'collisions'. We will also have a list of 'exceptions' for cases such when the word "на" is used with a one syllable word.
Thank you for your interest in our application. We might have some sort of beta testing session closer to the release date, but we still need to think about this issue. I will contact you via PM if we decide to initiate a public beta testing program.
While our software does build logical connections between words, this is done primarily to improve the accuracy of Grammatica. The highlighting feature that you mentioned is designed to allow people to focus on aspects of Russian grammar that they are having difficulty with. So you can have Grammatica highlight all other words with a case similar to the currently selected word. Thus giving you a better understanding of how a particular case (or any other grammatical characteristic) works.
Could you give me an example of what you mean by dividing complicated sentences into smaller parts? I just want to make sure that we avoid any confusion.