Same happens here with the 2017B version, not with older versions, so I use the GP4B 1.841 to rename textures, there must be an easisest way to disable the moving with keys that I donĀ“t know, but by now the only way to use those letters with GP4B 2017B (or what I do is...) open notepad, write the new tex name, copy and then paste it in GP4Builder...