http://iscoresports.com/

I mistakenly gave a hit to a player instead of an out in the forth inning, and didn't catch it until game was over, how can that be changed

You can override the stats to take away the hit. See the following link in the iScore FAQ:

http://iscoresports.com/baseball/kb/faq ... _edits.php

you can edit hits to errors and erros to hit in post game editor. but you can not change add/delete an out. that would confuse the software logic that expects three outs a half inning.