there are many ways to do it.
– you can make a supersized subcomp with all the credits inside and scroll this comp in the maincomp
– you can make a supersized text layer in your maincomp and scroll this one. unfortanetely you can only see the portion of the credits that are visible at a specific moment in time. another drawback here is you cant draw a bounding box with the text tool.
– you can break the text into some parts that make sense. and animate all this text with parenting to a null that is animated. dont parent all the text layers at the same time. do them step by step as they need to appear
– and still…many other ways to do it
good luck,
payton