Set Soller Shutter 3 venetian blind position after sendCommand(DOWN) completed

Hi,
I was reading bunch of threads about Fibaro Roller Shutter 3, but I am still confused. I can control my venetian blinds from OH, but I would like to set some rules. The very basic thing would be to close blinds and set slats position to an exact value in some circumstances.
Vertical positioning works fine with sendCommand() commands, but I have no idea how to set slats when vertical positioning have finished. Is there any solution to achieve this than creating a timer createTimer() function and wait for predefined seconds? I found that if I send the slats positioning command first, than I do NOT get the desired result. :confused:
Do you have any similar experience with RS3 and venetian blinds?
Thank you,