This video will cover the use of the position panel when your slide objects are either unlocked from fluid boxes, or if you are using Breakpoint responsive design mode.
You can still design responsive design using Breakpoints in Adobe Captivate 2017 and newer by switching from the default of Fluid Boxes to Breakpoints. You can do this from the Project drop down menu and selecting Switch to Breakpoint Mode. In Fluid Box Mode you can continue to use unlocked objects on your slide in much the same way as in Breakpoint Mode. Personally, I refer to this mode as Single Point Mode and it offers some nice advantages over the other two responsive design methods. Mostly it centers around the ability to still have objects over top of one another, but also offers the advantage of designing with a single view as in non-responsive projects (Blank Projects).