TS Recent Posts – limit number of posts

Hi there! i′m using TS Recent Post (recent posts showed on the sidebar) and i want to modify the number of posts. Unfortunatly in the Admin/ widget area i don′t have a “number of posts” parameter so i think i need to modify some php file but i don′t know wich one. I tried with sidebar.php but only got this:

[Code moderated as per the Forum Rules. Please use the pastebin]

hope someone can help.
thanks.
Rosana.