I just downloaded and checked the .deb archive and the migrate_apache script is definitely there, make sure you have the deb built today:
rm hestia_1.1.0_amd64.deb
wget -N https://apt.hestiacp.com/beta/hestia_1.1.0_amd64.deb
apt install setpriv
dpkg -i hestia_1.1.0_amd64.deb
On your second question, WebApps installer is a brand new functionality and indeed there are currently 5 apps implemented at this moment:
- Wordpress
- Prestashop
- Opencart
- Laravel
- Symfony
The remaining ones will get implemented during the next development cycle after we get some feedback from our users.