So the Max Travel is there to protect the focuser from moving beyond its bounds and damaging itself. So I would set it high enough that it doesn't get "in the way" of an autofocus run otherwise you'll get compromised (=poor) results. Focus will persevere and try to do its best but the constraint is just unnecessary. As a guide set it to at least 2 * number steps * initial step size. Personally, I set mine way above this so I know it won't compromise the autofocus run.
I would always start focusing from near to focus. You can do this quite easily manually or get close enough and do an autofocus run and then that's the start point for the night.
As far as the 5s guide exposure I don't know what's going on there. Sounds strange. I was messaging Jasem earlier and he confirmed that setting ZWO CCD driver in the Indi profile would handle both cameras (which is what I do BTW). Have you got the latest version of the driver?
Happy to take a look at your focus pictures when you next try things. I'm guessing you have a scope with a central obstruction, hence the tricky situation with out of focus stars.