And, were you able to get them to work? I installed the latest build, but every time I attempt to register them, I get a CRC error. I couldn't find any support address on the site, or what versions of Windows are supposed to be supported.

Download and Installation

If you are working with ...... then download, ...... and install
 
Cakewalk sequencers

• SONAR 5 to 8.5, x64 Editon (64 Bit)
• SONAR X1 or later, x64 Editon (64 Bit)

Midi Plugins 64 Bit (V8.60, 29.6 MB, updated Sep 1, 2015)
Run downloaded midiplug_64.exe
 
Steinberg Cubase 5 or later or later, 64 Bit
Run downloaded midiplug_64.exe and make sure to read the installation notes below
 
 
Cakewalk sequencers

• Pro Audio 8/9
• Home Studio
• Sonar 1 to 4
• Sonar 5 to 8.5 (32 Bit)
• Sonar X1 or later (32 Bit)
• Project5

Midi Plugins 32 Bit  (V8.60, 26.1 MB, updated Sep 1, 2015)
Run downloaded midiplug_32.exe
 
Steinberg Cubase Pro/Artis/Elements/SX/SL/SE/Studio 32 Bit
Run downloaded midiplug_32.exe and make sure to read the installation notes below
 
Ableton Live, Mackie Tracktion, etc. Not supported.
 
Windows hosts that only support the VST or VSTi standard are currently no compatible with the plugins. The midi functionality of these standards is too limited for the plugins. It is necessary that the hosts support VST-MA. Generally, the plugins will only work on Windows with the listed hosts above.

Using and working perfectly here with Win10 and SPlat x64.
If you are getting a CRC error, that's because the download was corrupted.
Use a download manager?

Dear friends, OP has clearly mentioned he is getting CRC error during REGISTRATION.
 
I have tested these plug-ins a bit under Win10/Splat 64, but I have not bought them. To reach the registration process, they have to be installed (and working) first. So the problem should be somewhere else.
 

They're working for me under Windows 10 and Sonar Platinum 64bit.
 
What's the exact error you're getting?

Try running the install "as administrator"

gustabo
Try running the install "as administrator"

I may try that. The plugs showed up in Sonar, but wouldn't allow me to register them. I went to do a reinstall, and there was no way to uninstall them in either the start menu or the program menu. I'll try and tackle it again tomorrow.  Thanks for the advice everyone.

Physically deleted everything tied to the install. I then reinstalled, and the uninstall showed up in the programs list. This time the serial worked with no problem.
 
Thanks again, everyone.