TechTool Pro 3 does not delete or use TechTool Pro 2 invisible files

Tom Kostes discovered (and we confirmed) that TechTool Pro 3 installs a new set of invisible "•TP3" files and folders, including a new TrashCache folder. This means that, for those that previously used TechTool Pro 2, any existing invisible files in the "•TP2" TrashCache will become inaccessible. It also means that these files will never be automatically deleted. For Tom, his old TrashCache folder held over 100MB of now useless data. The solution is to use a utility (e.g., Sherlock; File Buddy) that can display and delete these files - and delete them.