To Set the Background for Dimensions
You can use the options in the Entity Display tab in the Creo Parametric Options dialog box (File > Options) to set the color and transparency of dimension background in feature creation and editing. In Dimensions, annotations, notes, and reference designators display settings you can set the following options:
Dimension Background—Shows or hides the background for feature dimensions.
Always—Shows the background for dimensions when you define and edit features.
Hide—Do not show the background for dimensions when you define and edit features.
Legacy—Switches the display of the dimension background to the legacy settings. Applies when the option enable_transparent_text_bg is set to no.
* 
You can also access the options from the View tab available in the Show group. This is applicable only for the session.
Color—Sets the dimension background color.
Highest Contrast—Shows a black or white background for the dimension to provide a high contrast with the dimension text color.
Global Background—Uses the color that is set for the system background as the background color for dimensions.
Manual—Uses a color that you specify, as the background for dimensions
Transparency—Use this option to set the opacity for the background for feature dimensions. Type a value between 0 and 100. A value of 100 results in an opaque background.