Project Two: Image gallery revised

Today I re did my image gallery using some Java script. My original gallery wasn't able to be used in Google Chrome. I have now completed my image gallery. I had to use some code "javaScript=:void(0)" to stop the page linking to the top every time I clicked on a thumbnail. Everything was working perfectly in both Google Chrome and Firefox while at WITT today but when I came home and opened it on my laptop the images would no longer load with the "onClick" function but would if I changed it to "onmouseover". It makes no sense why this is happening. I have made sure that I am using the latest versions of each of the browsers. I am going to check tomorrow at WITT to see if it still works on the computers there using the "onClick" otherwise I will just change it to "onmouseover". Frustrating!!!!