I use VMM on a DS and Virtual DSM 7.0 Preview.
There is a change in the installation process in the new DSM 7.0, which usually runs in the future no longer as root, instead as user in the new lower privilege framework.
In DSM 7.0 in the package center both packages are available:
If I try to install the Safihre package (SynoCommunity),
I got the follow message (sorry for the german):
This means:
If I try to install the Kastelo package, no package is found:
With the result: