why don't you make it yourself?
make or get a texture you like, add an alphachannel (e.g. with PS), adjust the alphachannel, create a segments with a segment creator and add the files to your FPSC Folder
that can't be too difficult
i made some transparent segments but i stopped working on it... i wanted to make a glass corridor but i noticed that i can see the transparent corridor but nothing else... the engine renders just that, what you can see on your screen
--- This is not the best English, i'm from Germany
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