bX-cq8wks is a common error faced by bloggers on Blogger (Blogspot) blogs. Bloggers normally get bX-cq8wks errors while editing their widgets in Layout mode or after attempting to save changes made to their page elements (widgets etc) in Layout mode.
bX-cq8wks is quite frustrating for bloggers on Blogger and as of time of writing, Blogger has failed to provide bloggers with the proper solution to go around bX-cq8wks errors. Thankfully, I have found a way to go around it! :-)
In order to go around and solve problems that cause bX-cq8wks errors, bloggers must edit and change the position or layout of their page elements/widgets manually instead of using the convenient but buggy drag-and-drop functionality provided in Layout mode. To move or rearrange widgets/page elements manually, bloggers must use the Edit HTML sub-tab in Layout mode (must tick the Expand Widget Templates).
Before going any further, bloggers must know that all widgets/page elements in Blogger have tags that start with <b:widget...> and end with </b:widget>. To move page elements/widgets to some other locations, bloggers must cut (cut, not copy) the whole codes (from the starting tag to the ending tag as mentioned earlier) and paste it to its new location (new location should be right after the ending tag of some other widgets/page elements).
Once completed, bloggers can now click on the Save Template button to save the manual changes made to their page elements/widgets. If all goes well, the changes would be accepted by the system and you will no longer be bugged with those irritating bX-cq8wks errors.