Hi,
Your time conversion is ok. In the graph it looks strange, because all your timming is thesame, I changed the data.txt and now it looks ok.
Look at attachment.
Take some time to clean the code a little bit, otherwise it's much more difficult to read it.
Make some subvi's - select peaces of code and go to the edit menu and select create sub-vi.
Try to maintain data flow from left to right.
Regards,
Paulo