Welcome to the forums, iTracy! Happy to help.
Regarding the first question: one thing that may be helpful to know is that if you assign a start (or due) date to a project or action group, it not only applies to that item, but to all the items it contain.
(If a project is due today, then by extension, all the items in that project is due today, for example.)
That may explain some of what you're seeing - if there are other items that are still confusing, get in touch with our
support ninjas; if you send them some screenshots, we can figure out what's going on here.
If you specify a day but no time for a task, OmniFocus for Mac will have it start at 12:00 that morning. As early as possible on that day, in other words.
Regarding the sorting problem: can you help us help you by letting us know which edition of the app you're having trouble in, and whether you're in context or project mode? That'll give us more info that'll help explain what you're seeing...
Hope this helps, and happy to answer more questions...