Most important, you need to run everything in standalone mode before running as plugins.
A lot of the synths have a reputation for certain genres of music. Absynth for soundtracks, Massive for edgy EDM, Razor for dubstep. If you look through the presets, you will find that they are a lot more versatile than their reputations.
If you are using any of the Reaktor synth ensembles regularly, be sure to make a track template for each loaded ensemble. That will save you from having to load Reaktor and then load the ensemble.
For GR5:
- you should make sure you understand the advanced controls. They really can make a difference.
- Do the Craig Anderton EQ trick after speaker simulations.
- Pay attention to your gain staging
- Don't be afraid to try multiple amp and mic combinations.
- For traditional guitar sounds, I prefer either Reflektor or Vintage Reverb over Studio Reverb.
- The advanced controls on the MXR phaser clone make it a bit more versatile than the original Phase 90.
- If you don't like the chorus sound on the chorus/flanger, try using the modulation feature of the Memory Man clone.