Turbo cooling

["L. Scott Oliver" <SOLIVER@gcwf.com>]

Question for all you turbo gurus:

I drive my 5kCSTQ to work every day, up the freeway for 25+
minutes, getting into boost frequently.  The office is less than 30
seconds from the freeway exit (2 blocks); I drive in and turn it off. 
With the heat the turbo generates (increased when I go to IA
Stage 1?), I worry about the engine's ability to cool itself after
shutdown, even with the watercooled turbo.  Bentley indicates
the after-run fan and pump are limited to 10 minutes.

1)  Should I idle the engine for a number of minutes upon
arriving?  How many minutes? Or is the after-run system
adequate to cool it off?

2)  Is there any way to limit the engine's ability to produce boost
by controlling the wastegate (e.g., telling the computer it's
overheated and it should dial back boost)?  Would a "valet/warm
up/cool down" sort of switch be desirable?

The list is a fantastic help -- TIA!

--Scott