You can add them by inviting and please instruct your team members not to sign up because on signing up they will get separate admin accounts but not employee accounts.

Yes, the smart application also works in the offline mode and stores data in the system and sends it when the network is restored.

Application needs minimum 100kb/s bandwidth to work in online mode.

It is asking to make this application compatible with your windows version.

Please download the .Net version 4.0 from here -

https://www.microsoft.com/en-us/download/details.aspx?id=17718

And .Net version 4.5.2 from here-

https://www.microsoft.com/en-gb/download/details.aspx?id=42642