I have a new desktop built with all new Windows 8 OS, I went through standard steps of installing WCS V7 toolkit and it installed like a gem.
...so the word is out, Yes it works on Windows 8!! here is a quick log of installation steps.
Here is a tantalizing view of WIN 8 with WC Toolkit.
1. Install installation Manager 1.5.2
2. Install RAD 7.5.4
3. Update to RAD 7.5.5
4. Update to RAD 184.108.40.206
5. Install WAS 7 test environment
While installing WAS make sure you don't select a profile name as shown below.
WAS profile will be created when we install commerce development toolkit
6. Update WAS 7 test environment to 220.127.116.11 (Don't select any feature packs)
7. Install WCS V7 commerce toolkit
8. Update WCS toolkit with fix pack 6
9. Update WCS toolkit with feature pack 5
Launch toolkit and njoy it on WIN 8!!!