Step by step:
1. Create an account at https://www.multcloud.com/sign
2. Go to your account: https://www.multcloud.com/index.jsp
3. Open "Add Cloud Drives"
4. Select "WebDAV" and then Next
5. Config the WebDAV
Server (WebDAV Address): https://cloud.allsync.com/remote.php/webdav
Repeat STEP 3 & 4 And setup your new Pro account.
Your WebDAV url for the Pro plan looks as follow:
6. Open "Cloud Transfer"
7. Select the directory you want to transfer from Allsync Basic and to Allsync Pro.
8. Click "Transfer Now" to continue.
9. Open the status page.
10. Remove your cloud accounts from multcloud.com after you finish. Go to "Cloud Explorer" and Right Click at the Cloud service name.