Nope that is not the problem. See the notes at DD. We added a lot of notes to hacks for various reasons.
http://www.ztcdd.org/DD/index.php?topic=1437.0
- Only works for official in-game dinosaurs.
- If the hack does not work for in-game dinosaurs, you might have a version where extra bytes are at the end of the ".ztd", which confuses ZT. Rezip the ".ztd" to get rid of any extra bytes.
Jays pm to me today: (I have not updated the topic yet)
The version at ZA is still the original version where the ".ztd" has extra bytes at the end. 7-zip shows this when right-clicking on the ".ztd" and clicking 7-Zip->Test archive. So you can give that person a link to the above DD topic. But before you do, you might want to update that Notes post. The Description says to rename the ".zip" to a ".ztd", which may have been true at one time. But the download is a ".zip" that contains a ".ztd". So the ".ztd" would be extracted from the ".zip" and not renamed, although it still will not work in ZT until it is rezipped.
Edit: more from Jay: I just tested my rezipped version Penguino's No Egg Hack again. The Allosaurus has cEatsEggs = 1 and cLaysEggs = 0, and it was adoptable as adults. So cEatsEggs does not have to be set to 0. When VNDragon made that change, they had to rezip the ".ztd", and it was the rezipping that made it work.