I would like one transducer offset for the regular sonar transducer and one for the structure scan sonar.

My setup is:
Lowrance HDS Gen 1 with built in antenna close to the bow of the boat.
Regular sonar transducer mid ship.
Lowrance LSS-1 at the stern of the boat.

As I understand it it is only possible to offset the regulat sonar data as of now. Or am I missing something?

Actually to make this really good it should be possible to offset every channel in the .sl2 file since in theory every channel could have a source comming from different positions.

This is all planned/in development as part of a major overhaul of the sonar viewer in RM. It will be possible to have full settings control over every channel including x/y/z location, including port/stbd sidescan for the case where people run a separate transducer down each side of the boat.

Sounds great! Are there any rough time plan for this?

Still a way off unfortunately - towards the end of this year. We are releasing a standalone sonar viewer shortly which will have many of the improvements that will later be added to the full ReefMaster.