You must remember that CHDKs lmitations are down to the user and the build you use. I know I keep harping on about things like that but its true. So please do refer to the Wiki & the forum, I'm sure your problems will be answered there.
Apart from what I've mentioned on the other page and in the tutorial, there are a couple of items that might help you.
The scripts must carry the file extension .bas In Windows you can use Notepad to write your scripts. Then to save just select All Files and and enter your file extension. There is another way I used to use when hand coding html in the old days ;-)) Simply save as a text file if you have created it off the desktop, then click the file name once and pause, click it again. The name will be highlighted blue and the cursor will flash at the end of the name don't do anything other than begin to write in your chosen filename and extension, such as, myscript.bas and then click away from the file. Windows will complain but just say Yes you want to change it. It is a very simple way to switch between editing a file and executing it in this case.
Mac users however have a different problem. The Wiki has a special FAQ/Mac page which is worth looking at. Basically you can use the TextEdit to create your script but when coming to save ensure that you make it Plain Text Encoding: Unicode (UTF-8) and uncheck the box "if no file extension etc" write in your full file name e.g. myscript.bas and then load to your script folder on the SD card. I've noticed that if you use the Cover Flow method of viewing files, when you take the script file over to the SD card the file changes to Unix Executable in the Cover Flow window for the SD card which is what you want.