Importing PDF

I successfully imported a PDF to Musescore but there are missing pages
the PDF is 65 pages maybe too much info at one time messes it up?
Also it spreads the measures out very irregularlly
I would like 4 measures per line can someone tell me how I can do that
I'm a Finale user , new to Musescore
I've been searching the manual for these answers but can't find it