A text file is as simple as it gets. Basically remove everything that says "configuration file". You you just have the actual text that you wanted. Then use the Read Text File primitive to read the file.
So your file should look something like this:
1% HF 5% H2SO4 2% HCl 4% HCl 10% HCl 2% HNO3 10% HNO3 1% HCl + 1% HNO3 + 1% HF - 2% HCl + 0.2% HF + 1000 Flux 2% HCl + 0.2% HF + 10000 Flux 10% HCl + 0.2% HF + 1000 Flux 10% HCl + 1% HF + 1000 Flux 10% HCl + 0.2% HF + 10000 Flux
Notice there is nothing for a section or key. That's because you don't need it. Just read it directly. This will also make it easier for your users who have to edit it since they don't have to try to keep the configuration formating.