Version 9.1 > image effects
I didn't see a forum for 9.2 so I'm posting this here. I tried using image effects (contrast, brightness, etc) on an image in 9.2. The changes displayed in the dialog box but did not affect a change to the item on the display screen.
I discovered that image effects do change the displayed image when made in the global properties for images, but if made on an individual image in the program, those changes do not work - even if there are no effects set in the global properties.
I did (as I understood it) what you described, and was able to get the effects (Image Adjustments) to apply as expected to several different image types (bmp/png/jpg) when applied directly to the images in the program panel and view the result on the main projection output. You did not elaborate on specifically where you are looking for the change (Main projection/Stage etc) but assume it was the main.
As long as there is nothing else overriding the setting it should work as expected. I suggest connecting with the support team so they can walk through it with you to determine what step I may be missing.
Also there is a 9.2 forum in the Subscriber section - if you are logged in and current you will have access - scroll down to that section.