I also find that the quality of the dongle/docking station matters a LOT, and I've never found one that works reliably well :( You have to keep trying different ones until you find one that works... so far the best luck I've had was with OWC docking stations, but even that isn't always reliable. It sucks, coming from PC where that's all worked fine since like... 1999.
As for the modifier keys, I don't quite understand the problem. Are you saying things like shift-click or opt-clicking no longer work? Or the OS won't detect more than one mouse button held down at the same time?
I don't know if your mouse has special drivers, but one idea is to see if maybe you can use Automator as an intermediary? e.g. have the mouse send either a special key combo that Automator can pick up (or if the driver allows you to, to run a special command), and then have Automator send fake keystrokes to the target app? There are also third-party software like https://macmousefix.com/ that might help (never tried, just a random search).
I also find that the quality of the dongle/docking station matters a LOT, and I've never found one that works reliably well :( You have to keep trying different ones until you find one that works... so far the best luck I've had was with OWC docking stations, but even that isn't always reliable. It sucks, coming from PC where that's all worked fine since like... 1999.
As for the modifier keys, I don't quite understand the problem. Are you saying things like shift-click or opt-clicking no longer work? Or the OS won't detect more than one mouse button held down at the same time?
I don't know if your mouse has special drivers, but one idea is to see if maybe you can use Automator as an intermediary? e.g. have the mouse send either a special key combo that Automator can pick up (or if the driver allows you to, to run a special command), and then have Automator send fake keystrokes to the target app? There are also third-party software like https://macmousefix.com/ that might help (never tried, just a random search).