Complex Javascript Problem

[scanet]

Hello, I am having problems with my website, there is a nice bit of javascript on it but it partly works and partly does not work. The user must click on the bare system to continue which is fine, the problem is if there is only one item in one of the sections section as the bare system and the floppy drive, if the are checked and submitted the items will not be carried through to the next page but if there is more than one item the code workes fine. help would be greatly appreciated.

The code is too long to show view the source at:

http://www.comsco.co.uk/comsco/system_build.asp?model_name=CF7789

Thanx

Glenn