[Typo3] TemplaVoila! and standard HTM-template based sites on one isntallation

[cyprian.pl]

Hi,

Is it possible to have two sites based on these two template concepts on  
one installation?
I have a dummy typo3 installation, I did the Modern Template Building  
tutorial, and now I'm doing TemplaVoila! tutorial and I've noticed that  
the pages from MTB tutorial don't show up in FE.
Is this normal or it's just me - a Typo3 newbie?
I guess there is no way to dynamicaly load extensions for each site?
Do I have to have separate installation for different sets of extensions?

best regards, cyprian.pl
[http://pi2.pl] || [http://cyprian.pl] || [www.opera.com]