It's always best to leave the workflow and mindset of another application behind once you start with new one :)
1. If I recall correctly, most of the people preferred to have polygons render always... something that you can use is to apply completely transparent material and load a selection into it, although I would prefer hidden polygons not to render too.
2. Not sure what is troubling you but keep the following in mind. If your selection tag is active, anything you have selected at that moment and you hit "set selection", that is exactly what will be stored. If you want to add to selection, simply double click the tag and then use shift or ctrl clicks to add or subtract from selection, then hit "set selection" again. If you want to make a new selection make sure no selection tag is selected so that new one is created.
3. Keep in mind that you are disabling the object in viewport, so you can't select it in viewport but you can through object manager which is not the same. You can of course enter component mode but this should not automatically unhide the object. Imagine you click in empty space in viewport when you have a couple of hidden objects while you are in component mode and they start appearing and you hid them to access other objects? that would not be fun :)