How are you trying to change the color of the gradient.Can you please mention the steps that you are doing which results in elements being locking up.
The steps taken to change color are :
1 - click on gradient thumbnail in the layers panel
2 - click on the gradient colour box on the gradient fill box - this opens the gradient editor box
3 - click on the coloured ikon below the gradient profile- this enables the colour change box at the lower left of the gradient editor box.
This box has two options :
1 - click on the soolid colour within the box - this opens the "select clour box" and any changes made here are successful.
2- click on the down arrow at the bottom right of this colour box. This opens the "clour swatches" panel and this action alone locks up Elements 11 requiring the programme to be closed down and re-opened.
I hope this helps with any answers you may have.
Thanks for taking an interest.
I tried and could not reproduce it at my end. Could try launching elements with clean preferences. Go to
Win - C:\Users\[YourUserName]\AppData\Roaming\Adobe\Photoshop Elements\11.0\Editor.
Delete everything in this folder and try relaunching PSE.