Well... I don't understand the instructions either lol... see, this is what it says:
"double-click on quickbms.exe"
Done that.
"select the script or the plugin for the type of archive you want to extract (for example zip.bms if it's a zip file)"
I did that, I opened RTB's "lzh8_dec" script file.
"select the archive or multiple files":
I selected multiple .CX files.
"you can also select a whole folder by entering in it and then typing "" in the "File name:" field and pressing Open"
I tried that, and I typed in "Battle" for the folder name.
"select the output folder where extracting the files (you can specify any file, it will be ignored because only the directory is taken)"
I'm not sure about this step now.
watch the progress of the extraction
Obviously, I couldn't witness this step because I couldn't get it to work.
Anyway I clicked Save and it showed me
this.