Trial supposed to be fully functional. what exactly is the problem? we need much more information
What tools? Some are only available with certain types of footage. For example, you cannot motion track a photograph or a shape layer even if you animate it. You can motion track a nested composition because that's a movie, even if there is nothing to motion track in the nested comp.
If you are new to AE you should start here: Basic AE
How can I fix this?
You read the help. As the others said, several tools work only within a specific context and require the correct footage types to be used.