Hi cloudsplitter,
An Internet connection is required the first time you install and license your desktop apps, but you can use the apps in offline mode with a valid software license. The desktop apps will attempt to validate your software licenses every 30 days.
For annual members, you can use the apps for up to 99 days in offline mode. Month-to-month members can use the software for up to 30 days in offline mode.
In case of very slow Internet connection try the direct download from any place with good Internet speed, copy app's on the hardisk and then install it on your home machine. Sign in and activate the subscription.
Direct link: http://prodesigntools.com/adobe-cc-direct-download-links.html.
Kindly follow the very important instructions before download.
Refer the article: http://helpx.adobe.com/x-productkb/global/troubleshoot-download-problems.html#main_Estimated_download_times showing estimated download time.
Regards,
Romit Sinha