You need a newer version of the Lego Fantom Driver.
You can download it here as part of the whole software kit:
If you want JUST the driver on it's own, scroll to the advanced section at the bottom of this page:
And grab the NXT ...
I'm sorry you've been frustrated with Blender. It is complicated and not as intuitive as it could be, but the alternatives are vastly more expensive for slightly better UX. 3D modeling is a lot of learning, regardless of the tool. Blender seems to be the best free general 3D modeling package available. There are tons of tutorials out there and Blender.SE ...
I haven't tried creating my own parts. However, I've seen that Bricklink's PartDesigner is quite popular in the community. It looks like the creation process is quite streamlined, you can edit the connectivity info of each piece, and it plays very nice with Bricklink's Studio.
Create a new MyBlock and delete the old MyBlock.
So, you have to create a new MyBlock with a different name and move all the programming to the new MyBlock. Then delete the old MyBlock and replace the old MyBlock with the new MyBlock. This did work for us.
The "App" page does seem to be hard to find at the moment. I found it by clicking on this little icon on the MINDSTORMS "About" page.
The app is distributed through various app stores:
Microsoft Store (Windows)
Apple App Store (macOS/iOS)
Google Play (Android/Cromebook)
Amazon App Store (Kindle Fire)
There isn't currently any option ...