Saw the Release Notes of 7.1.3 that Enhanced Support for UEFI High Resolution Screens was introduced. While it filled out the screen accordingly on the Surface Pro the OSK still doesn't function. Is there anything special to get it to work that I missed? I went into the Policy for Product Settings and told it to Enable the OSK but that was a no go, then selected always show the OSK and then it shows on the screen but doesn't function. The pen does work in the BIOS type screen but not at Pre-Boot and then works again in Windows. This is one of the Original Surface Pro devices. Is this still a Firmware Issue?
There is a known issue that if TPM is enabled the OSK will not function. This is documented in KB84563 and requires a Microsoft firmware update.
Looked at that article and that refers to the Surface Pro 3. I was testing with the original Surface Pro but with the Tablet Test it fails to find any EFI_I2C_IO_Protocol. I did try turning off TPM but no luck.
The Microsoft Surface Pro first generation will not have support for Absolute Pointer Protocol (finger/touch device). When the Absolute Pointer protocol is not present, the end user cannot access the On Screen Keyboard controls, mouse or using their finger or a stylus. - KB79624
The protocol is a part of the Microsoft UEFI firmware. Without the protocol, the UEFI Preboot application cannot communicate to the touch screen. Microsoft added this protocol to the Surface Pro 2 and 3 models.