add ons central when you load the app will get you there, i believe?
can google 'site:
www.ootpdevelopments.com' -- it's been a while since i downloaded an updated roster, but there are other posts with more verbose instructions, if you run into a snag, or what i say just isn't real...
it'll be a league template file that you want -- wherever you find it. if you want it to be default, delete existing default template and rename appropriately in the world_templates folder [sic]. next time you try to load a default mlb league, it will be the updated roster release.
i can't help with the other stuff. no, a cap is not default. settings->finance tab.