1) Prior to make any change in style, need to ensure that style set to Read/Write in project dialog box. In order for this to work, we have to have write access to the styles library. This is generally controlled by our project file (IPJ). Please see the attached screenshot file “Project Style Library_ Example.JPEG.”
2) Do the necessary changes in the style or create a new style, enssure to save and update the same in the template. Once you have saved the changes to the style library, need to ensure that all the template files' local styles are up to date. This is when we use the Update Styles command. Then either we open our template file, hit Update Styles, overwrite the local styles with the library styles, and save the template or we can save and update new templates with custom style.
Please see the attached screenshot” Style editor save and update example screenshot.”
3) Please use Save copy As Template and save the new template files into the template location. Now, if you close this file and re-open the template, should not get any such massage and would get the new custom styles also. Please see the attached screenshot” Template location Screenshot.”