Their versioning is completely incomprehensible!
The TL866CS is the original programmer and has a max Vp = 21V
The TL866A is a version that supports serial devices, Vp max = 21V
The TL866II is a recently released version, Vp max = 12V18V it seems
It's sometimes called TL866II Pro, or Plus, or just TL866II.
In addition, the software is for the TL866II, but supports the A and CS. The A and II support slightly different devices. (The A is a superset of the CS.) The II (software) supports everything any of the devices support. That's the truly confusing part.
It would have been so much easier to use different product codes, say TL866, TL870, and TL880. Then call the software "Device programmer for the TL800 series". ONLY list chip support for the programmers, under the obvious assumption that the software supports all chips for all programmers its supports (what would be the point otherwise).
I mean, like any sensible business elsewhere in the world would have done. So given a device you need to program can easily figure out which programmer and adapter to buy, then just download the software and hit to GO button.