The following information is MY PERSONAL imagination. It is based on a little bit more then a "rumor from the internet", but since I have not went throw the whole procedure to prove that (yet), some statements can be wrong.
The problem of the driver is NOT that it does not mention windows 10. The problem that it DOES mention
never existing version of windows. That is why many old drivers install without any pip, which Roland drivers require "the hack". Explicitly, the problem is:
[Roland.NTamd64.6.2]
;; Windows8
%RDID0106DeviceDesc%=RDID0106Install, USB\VID_0582&PID_0117 ; VS-20
[Roland.NTamd64.7]
;; not supported
64.6.2 is Windows 8; 64.6.3 is Windows 8.1; 64.10.0 is windows 10; 64.7 ... does not exist!
What this statement means for Windows? That the driver is ALLOWED to be installed on ANY version between 6.2 and 7. Effectively on Windows 8 line only (so Windows 8.1 is allowed, Windows 8.5 is also allowed... but MS has moved to Windows 10 instead).
Without 64.7 section the driver could have an "open date" and be installed without problem. But in current situation,
Roland has per-programmed the drivers and so devices will be obsolete during the time they was making them. They put a "time bomb" there.
Was that the Evil plan? I do not think so. They was releasing separate drivers for separate Windows version. I guess that was to avoid users by mistake install let say Windows Vista drivers on Windows 8. And as long as new drivers are released that is good. But I think they had to release the driver with open date when they have made the decision no longer continue the development, removing the time bomb.
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Now to the latest discussion. The signature is checked during the installation and during loading. But the signature is PER FILE. There is a separate file with signatures for all other files. By described procedure, we modify only INF file, which describe how to install the driver. So its signature is not longer valid. The driver itself (binary files) still have correct signatures. So we have to disable signature checking during installation only, when the file with broken signature is used (the last sentence I have not checked, so like 95% sure...)
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I have installed the driver disabling signature checking during reboot. I had to do this again after anniversary update. I am sure the signing was/is on after the installation and I am sure my VS-20 is working.
I have not found any method to disable kernel level drivers signature checking without going into the "test" mode, which is clearly visible when on. So if you do not see you are in the test mode, drivers are checked on loading.