Hmmmmmmm, from what I can see on my pump/recall from doing my own settings, the LAST time block in a 24-hr period picks its own time made up of latest programmed time up to 0000, which you then need to fill - I THINK - so to use your example as an example there SHOULD - I think - be a last time block of 1800 - 0000, which you could now 'fill' with the 0.36u you're after.
I set all my blocks on the pump rather than the software. I'm not all that au fait with the software and only use it to download data for appointments - when I say 'I', I mean 'my husband'.......