Using Windows 8/10 Metro Apps with a Domain device - no local MS Account bound

I need to find a way to manage and allow the use of Windows 8 and Win10 metro Apps without binding a MS account to the device. These are domain machines and no personal accounts or integration is allowed at this customer. My goal is to figure this out and I have both a Win8 Surface Pro 3 and a Win10 Surface Pro 3 to play with.

With that said:

1) I saw posts on Google related to using alternate, generic credentials. I see the place to add these, Control Panel-> User Account-> Manage Credentials-> Windows Credentials-> Generic Credentials-> Add. I created one on a Win8 machine but I am still unable to load the App Store to even test this out. The tile for all Apps, including the Store App, have the fully expected 'x' in the corner, meaning I cannot launch them without having a MS Account bound as a local User. This means I also cannot launch the Store App to see if the generic credentials work.

2) I also saw mention that when you get to the Store you can select to use either one of the accounts on the device, or you can select a MS account. I was able to get to this on a Win10 machine but when i select 'use a Microsoft Account' the pop-up goes blank and hangs. i can close it without issue but it does not load the App Store.

3) Another idea was to create company-owned live.com accounts for each User and bind things that way, but this opens a slew of issues the customer does not want to get involved in. Such as the ability to file share documents via OneDrive. Sharing documents is something the customer does not allow and this alone is enough to halt the use of that option.

4) Another thought was to have a single, master live.com account that is bound to ALL of these devices, with a shared password among the Users. This email would be configured for Outlook for IT using the hotmail connector so they can monitor activity and purchases, as well as to see the contents of OneDrive etc. However, this is maint. i don't want to force upon IT when other options, if any, exist.

Does anyone have any workarounds or solutions?