If you use TOPS Professional Hosted, it is still possible for you to enjoy a customized desktop for your TOPS using Themes! Here's what you need to do to:
Go to the Theme Manager on your LOCAL machine (do not click the theme manager link inside TOPS Hosted, this step has to be done on your computer)
Download the theme (or themes) you wish to use. Save the downloaded zip somewhere you can find it easily.
Navigate to the downloaded zip files. Right click on the zip file and select Extract All To… (the wording may be slightly different on yours)
In the folder where you unzipped the file, select the theme files by holding CTRL and clicking each theme file (Each theme will have a folder and a preview image of the same name. You only NEED to copy the folders, not the preview images, although it will not hurt to grab the previews as well.) Right click on the selected files and select "copy"
Log in to the TOPS Hosted. From the launch screen, click to log in to the CLOUD DRIVE. If you cannot see your Cloud Drive folders, click on "Folders" on the bottom left.
In the cloud drive, navigate to the TOPSSoft/themes folder. Right click to paste the selected theme files into this folder on your cloud drive.
Log in to TOPS Hosted
Go to Customize > Themes. You should see your new theme in this list. Click the name to apply the theme.
Close TOPS and reopen it before attempting to set a theme