Can I start with new page numbering in different places within one
presentation?
This isn't possible in Microsoft PowerPoint. If you want to start a new series of page numbers within a presentation, create another presentation for those slides and link to it with a hyperlink.
My hidden slides are still being counted in my slide numbering.
To avoid this, you might try the following:
Can I create a header or footer that automatically shows the network path and
file name of my presentation?
This can't be created automatically in Microsoft PowerPoint; instead, you should type in the path and file name as a header or footer and update it manually. On the View menu, click Header and Footer, select the tab you want, click Footer or Header as appropriate, and then type the path.