When I wanted to build a certain psionic monster in GCS, I found out that the Psionic Powers library that GCS has is something of a hack job. Instead of giving you full ability builds, you are given abilities are prebuilt packages that you cannot adjust. Thus, I decided to make a proper library myself. Now, you can take any psionic ability and adjust it in any way you'd like.

However, you may notice some differences in point costs. Most of them are related to how GURPS Psionic Powers calculates costs for abilities that deal partial dice of damage. The book intentionally omits one step of rounding, which isn't something you can do in GCS. What you see in this library is what it is supposed to cost with proper rounding. In most cases, the difference is very minor, but sometimes it is noticeable. In certain other cases, the costs are different because the book has miscalculations. Later on, I'm planning to create a library for my own psionic abilities with all the houserules and new/altered stuff.