Typical workflow for HDR goes as follows:

Import into Lightroom

Correct WB if necessary

Export to Photomatix

Export Tonemapped TIFF to CS4 along with 0 EV RAW as Layers

Noise Reduction

Topaz

Mix 0 EV RAW as needed

Color Efex

Silver Efex if applicable

Levels

Sharpen

Save as TIFF