To answer your questions:
In m.62, what you have done is OK since it moves by step and is resolved into an imperfect consonance by step and by contrary motion, so that is handled correctly. However, you've broken a rule getting into m.62 by not moving by step in opposite direction after a leap larger than a third. An easy solution would be to start your counterpoint at the unison.
Skipping into an octave by oblique motion on the 2nd beat is OK under normal circumstances, however, it leads to a really, really ugly ending for your counterpoint - all those leaps up to the leading tone! :O
Other Errors:
- line direction m.61-62
- sequence m.63-64
- unresolved Bb m.64
- successive skips m.64-65
- too many notes in one direction m.65-68
- skip and step in same direction m. 65-66
- leaps too large m.68-69
- successive skips m.68-70
- outlining a dissonant interval m.69-70
Also, read my post here about use of accidentals in counterpoint, it may clear up some of your confusion.
Lastly, the occasional counterpoint question check is okay but make sure your questions can apply to a larger audience and not your homework assignments - as a teacher, I grade enough students' counterpoint exercises as it is (plus it's less helpful for other people coming to SE for answers!)
Hope this helps.