Here is an article from Akai's forum that explains how to set this device up inside of Studio One.
http://community.akaipro.com/akai_professional/topics/how-do-i-set-up-midi-control-mode-for-the-mpc-studio-in-presonus-studio-one
If the ports are not showing up on your system, you will want to contact Akai to troubleshoot.
Should there be an issue with your Studio One installation, you can try uninstalling and re-installing Studio One. You can also remove your settings files from Studio One and re-configure your External Devices. Here are instructions:
1. Go to Help>Open Settings folder.
2. Copy the contents of the folder over to a folder on your desktop.
3. Close S1 and delete the contents of the settings folder with the exception of the user.license file as well as the "Extensions" folder.
4. Open S1 and go to Studio One>Options (Preferences on a Mac) to reconfigure your settings.
5. Test to see if the problem is resolved. If it is not, please feel free to copy your settings files back over from the backup that you created in step 2.
*If you are missing presets or Sound Sets after doing this, simply double-click one of your Sound Sets under Documents>Studio One>Sound Sets.
If you continue to have an issue, please submit a support ticket with PreSonus. Just log into your my.presonus.com account and click the option for "Support."