Hi Mark,
In my case I worked with the Adobe Lifecycle Designer as a standalone application. So I exported the form from the C4C cloud solution, then imported it in ALD then repeated those steps the other way around to upload it back into the cloud. So I cannot tell if it would work fine with SAPlogon Gui.. I assume you can connect the ALD application with an interface to the ECC system. I do not have that knowledge.
You can check out this discussion: How to implement adobe live cycle designer on A... | SCN
Hope this helps.
Cheers,
Rogier