The analysis tool works with the imagery at its fullest possible resolution (at most this is 3600x1800 for a global image). As a result, if you are analyzing three global images it is possible that this might affect the speed of your web browser due to memory constraints of your computer.
If you notice that your web browser is operating slowly when using the analysis tool, you may choose to reduce the size of the files you are analyzing. One way is to not use global images and instead select a region for analysis using the "Select Area" map. The second way is to select lower resolutions using the "File Sizes" pull-down, especially if you must use global images for your analysis.
If you continue to have issues, please contact us.