My language is English, US.
Keyboard layout is English, Nederlands
Hardware keyboard only.

I made an interesting discovery by accident.

In applications that work right, I usually want, for example a capital P, so I press Shift then p. If I want 0, I press Blue Shift + p or press and hold p, I also get 0.

In applications that don't work right, I press Shift then p, it doesn't work, I get small p. I want 0, so I press Blue Shift + p. It doesn't work, I get small p again. I press and hold p, it doesn't work, I get pppppppp instead of 0.

However, in applications that don't work right, I just found out I can get a capital P by pressing Shift + p at the same time. If I want 0, I have to press Blue Shift + p at the same time.

That helps, but it's still bad. Some keys (a, z) are too close to Shift, pressing them at the same time is extremely inconvenient.

Besides, I can't find a way to enter a new line in my Tk app. I press Enter and nothing happens. Sigh...