One of the best features of the T1 is its ability to download direct from libraries which are part of the Overdrive system.
You can still use ADE to download your ebook purchases from places like Mills and Boon. Then just drag and drop the EPUB files onto your T1 using Windows File Explorer or Mac Finder. You do have to register your T1 to a Sony account which has the same email address and password as the Adobe ID that you use with the ADE software.
You can register to the Sony store wirelessly with your T1 without the need to use the Sony desktop software. At least you can if you are in the US or Canada. Possibly the UK too now that they have a Sony bookstore.