Thank you for bringing this to our attention. Have you found a specific maximum size limit (in bytes)?
I am not aware of a limit to the capacity of Utilities.TransferData, and short of updating Formativ, I do not know of a way to increase this capacity. However, I will add your request to our enhancement database for Formativ.
For the moment, I think the only alternative is to download the data once, save to a disk file and make the file available to all relevant applets. If security is a consideration, use Utilities.DESEncryption() to encrypt the data before saving to a file.