Simply rename the desired profile txt to the same name as shaderpack zip and delete the old one
(For example if the shader pack is ComplementaryShaders_3.12.zip, it's profile file is ComplementaryShaders_3.12.zip.txt)
You can also open the ComplementaryShaders_3.12.zip.txt, clear all contents and copy paste your desired profile's content into it
After doing this restart your game