It’s important to understand, that some Windows tools are 32-bit, while others are 64-bit. If you install OpenSC, then you need to install the 32-bit and 64-bit version.
If you install our own sc-hsm-middleware, then the 64-bit installer puts both, 32-bit and 64-bit DLL and executables on your disk.
To troubleshoot this Microsoft madness, I usually try certutil -scinfo in both version (available in C:\Windows\System32 (64-bit) and C:\Windows\SysWOW64 (32-bit).
Btw. the minidriver from OpenSC is a R/W driver, while the sc-hsm-middleware minidriver is a read-only driver.