@ferdinand and, do you know how to make a button hightight with a blue background like the attributes manager when selecting a panel？
edit: Forked form Add a GUI Button (by @ferdinand)
thank you for reaching out to us. Please remember to open a new topic of you own when you have a question and not to hijack other topics. The exception to that rule is when you have a question that aligns exactly with a currently ongoing topic. The reason we enforce this, is so that the form remains a nicely searchable knowledge base. I have forked your question for that very reason; it did not align with the other topic.
About your question: It depends on what you mean by it. You cannot modify the background color of a Button element. What you can do, is create a LONG element and define QUICKTABRADIO as its custom GUI; here is how the muscle object in Cinema makes use of this GUI element:
SCALE_H; ANIM OFF; PARENTCOLLAPSE;
This will give you the tabs look as shown in many places in Cinema 4D. You will however need multiple elements to make this useful, as this is effectively an options group. What you could also do, is create a BITMAPBUTTON and then have different images for its normal and pressed stated.