In south Texas we fight mold and mildew.I want the best option for avoiding this time consuming problem in a newly remodeled bath. We are installing a walk-in shower with a glass block entry wall, 3 walls shiny porcelin tile and bottom of travertine 1"x2" tiles. I was considering using epoxy with Microban additive. Any suggestions greatly appreciated.

For the shower part; I would use the Schluter Kerdi membrane system. That would put a waterproof membrane directly behind your tiles. No water would get past this point resulting in shower walls, & floor drying out much quicker.
Laticrete's Spectralock grout is an excellent easy to use epoxy grout. Would definitely help with the mold issue.
As far as the glass block goes. I've never needed to get creative enough to use epoxy there; but I think a high quality sealer used on the joints would help.
To find more information than you'll ever need concerning tile. Go to:http://www.johnbridge.com/vbulletin/index.php?referrerid=27552
Here you'll find all the info and help that you can use to do anything when it comes to tile.
I suggest you check out their "World Famous Liberry"

The task took some doing but finally found Spectralock Pro for the project. The shower is ready for tiling. Travertine is sealed, all tiles should be installed tomorrow. It may be a few days before the blocks begin, will use glass block mortar for that. Thanks for your help.