Creating tidal offsets for a secondary port in" Absolute Tides"

[Slocumotion]

Absolute Tides has a number of secondary ports but unfortunately it's "St Mary's" is the one in the Scilly Isles not the one in Orkney - so, how to create a custom secondary for my one?
AT requires MEAN High and Low waters at Springs and Neaps, and time differences between H and L water at the reference port and the custom location.
I have a tide table for my St Mary's so my thought is to find dates and times on the standard port (Aberdeen) table when heights are equal to the mean figures given in AT (for Aberdeen) ; take the figures from my St Mary's table on those same days for the nearest high and low tides, and enter them. Similarly for times.
My question is simply, do you reckon that will work?

Secondary question. How do others make full use of the tidal stream data when your Tide Table doesn't give you Mean values for your Reference Port and you therefore don't know the tidal factor for the day?( As far as I can see, the mean figures are only given in the setup screen for creating the Secondary).
I thought it was considered bad form to start estimating and rounding that early in a calculation.

 

[FWB]

Sorry can't help directly but if you have an iPhone / iPad then Tucabo Tides Planner has what you are looking for.
This is showing heights in feet but you can select metres. The red section shows when height is below 6ft, just the way I have it set up. Tidal currents are also available within the app.

Currents

 

[nickd]

Try looking at some of the other main ports around and see if St Marys is linked to that, ie I expected Barmouth my home port to be secondary to Holyhead or Liverpool but it was secondary to Milford Haven

 

[Maxi Windsong]

If you select Wick as your principle port, and then go to the menu to set up a Secondary Port, St Marys is one of the sSecondaries you can set up, which I imagine will be the one in the Orkneys, not the Scillies

 

[Slocumotion]

If you select Wick as your principle port, and then go to the menu to set up a Secondary Port, St Marys is one of the sSecondaries you can set up, which I imagine will be the one in the Orkneys, not the Scillies

Yes indeed, thank you. And better even, Widewall Bay is given as a secodary . That's literally lapping at my doorstep (hence the requirement for very local tidal information)
Still a bit of a problem though - I set up ("create") the secondary but can't seem to display it . Reverts to Wick again. There must be something I'm not seeing.

 

[Burnham Bob]

Change source data should give you the port you want. I like this app because the developer provides fast and excellent support. if you are stuck send them an email from the google play site.