I want Groov and SIEMENS PLC to exchange data

I want Groov svr for win R3.4 and SIEMENS PLC S7 to exchange data.
I know I need to buy GROOV-SVR-WIN-BASE+GROOV-LIC-ENT. Excuse me, do I need to buy another KEPServerEX?

Or use a groov AR1, it has the S7 driver built in.

How to use it to achieve data exchange?

S7 is very similar to this.