Pre comping layers with nulls

[An28710749opic]

Hello,

Usually when I am making an edit I pre-comp my clips before I add the nulls but this time I forgot and now I can't add the effects connected to the clip in the pre-comp. When I try to pre comp the clip without the nulls the transitions got messed up and zoomed out. How to I fix this??

[Mylenium]

What are the Nulls even used for? You need to explain better and provide screenshots.

Mylenium