If you run into problems try these steps:
1. Install Samurize in XP mode: right-click on install exe, Compatibility tab.
2. For audio plugins, you may have to run them as Administrator. Make sure DirectX is installed.
3. For SpecGP, read the notes on audio input/output settings. In spectrum analyzer mode, if the bars move a bit with no music playing, try reducing sensitivity to quiet sounds ("Nonlinear response") and check if the mic is not picking up ambient noise.
4. Some plugins require NET 3.0. You may already have it.
5. To isolate any problems, start the sample config in its own instance:
Client.exe -i=ConfigName -c=ConfigName.ini