Software for designing sequences

You are fully right - there is an open Linux available. Unfortunately, I have no experience programming the controller with Python etc., but only with CODESYS. Anyway, with CODESYS it works fine

Did you use the 'vanilla' brand - or the Wago version, and if so what version?

Say as an example I want to program Mfr. Part No. 750-882

What would I choose from the following:

Software
Stock-No. MPN Description
667-9255 759-302 Software WAGO I/O Check 2
882-0338 759-302/000-923 Software WAGO I/O CHECK 2 and USB Kit
509-6090 759-333 Programming Tool IEC 61131-3 WAGO I/O PR

I strongly suggest Smart Draw https://www.smartdraw.com/

Its the best for making any kind of diagram and has a plethora of templates already made to download for almost anything you want to do.

I use it for all kinds of diagrams and to produce machine documentation.

Download and try it on the full-featured trial. I guarantee you won't be disappointed.

Not the original question but if I have the choice of standard Codesys and manufacturer version I would always use vanilla.. Why.. I have used IFM controllers with Codesys works good but then you see that they doesn't support symbol configuration.. Not easy to use other brand of HMI.. Used Epec controller with Codesys.. that one didn't use Codesys standard functions for Can open... I hope that Codesys like Android forces manufacturers to support a minimum set of functions otherwise Codesys gets a bad name when it's really not Codesys fault..