I started working on Free Energy calculations recently and the example scripts included in the lammps distribution were a huge help for me. Thanks a lot for that!
I discovered that the data.lmp file used in the CH4hydr example has a mass of 4.008 for the methane-H. The version I am using is 23Jun2022.
Although such a typo is probably not the most pressing issue, I wanted to mention it anyway and say thank you at the same type for the helpful example scripts!