Confused on making a hack

[Bigcatkeeper]

Im trying to make a hack so I can edit zoo walls. But im not sure how I should get it so ZT uses the new updated files edited by me instead of the file already in a file like entities.z2f.

For example if the file I have edited came from entities.z2f, should I extract entities.z2f to a folder replace the original file with my edited one and then zip it back up?

Is this how hacks are done?

Thanks

[mikaboshi]

The way I do my personal hacks is to create a .z2f with files with the same name in it, and then name the .z2f Z-Something. For instance, say I make a hack for the Nile Monitor to have a correct number of babies. This uses a beh file, and is in ai\tasks.  So for the Nile Monitor file, I would want to make sure it was in a folder called "tasks" which would be in a folder called "ai." Zip this up and make it a .z2f starting with a Z so that it overrides the original game file instead of having to edit the actual files. Plus, if you ever want to get rid of it, you simply just have to delete the .z2f you made!

[Bigcatkeeper]

Where would I put the .z2f file. In the main ZT directory or in the downloads folder?

[mikaboshi]

main directory