When focussed it is possible to navigate the Tool Settings Dialogue with the arrow keys, moving the dotted outline around titles and using SPACE to open dropdown menus or check/uncheck boxes. However, the navigation is inconsistent tool-to-tool where sometimes navigation will get stuck in some settings and navigation is lost. The primary culprit is any tool that gives an option for Fill Colour, such as Place Block.
When using the up/down keys the Fill Colour dropdown opens automatically and navigability is lost. Yes, Left/Right arrows can also be used, but in some tools, such as Place Circle the navigation jams that way too...
There is also no way to expand tools settings, such as Modify Element with keyboard controls.
I noticed that in many tools from Day 1 of using Connect Edition (I think it was CE 2). Filed several service requests but guess what - nothing ever happened.
Just open the context menu when placing a cell and try to jump back and forth through the fields just with TAB/SHIFT+TAB.
Open the context menu of scaling, change the method by space bar, Enter key and see where the focus goes to - nowhere.
I could tell you lots of other instances where this happens. Fwiw, I told Bentley these years ago but they never changed a thing.
It's infuriating how many commands MicroStation tries to force mouse usage for and in equal measure how many they prevent mouse usage for