WPMUSite Inatallation in root folder and subfolders

Hi,
i want install Wordpress Multisite on my rootfolder /public_html/root-domain
and other 3 Installs of Wordpress Multisite in these folders:
/public_html/wp/domain1/
/public_html/wp/domain2/
/public_html/wp/domain3/

Then i want use your Plugins Domain Mapping and Multi Domains to give the users the possibility to create their own websites as subdomains-sites on the different installations.

A user, logged in on the rootDomain should be able to create a subdomain-site of the rootdomain
A user, logged in on domain1, should be able to create a subdomain-site of domain1
and so on...
Can i do that, and how i have to configure right to achieve my goal?
thanks!!