Hello Trevor,
Please see this link for the direct download of 4.5: https://condoctools.com/index.php?eddfile=7988%3A7469%3A0%3A0&ttl=5151530824&file=0&token=c58da01c00ca3f62d517264305534b3a
Once downloaded, you should be able to install it in SketchUp and enter your license to activate. Hope this helps!