Why not?
I doubt that's the problem. It does work on another computer. Some things I noticed:
HiDPI isn't supported. Why not?
Escape key doesn't work in Settings dialog.
Enter doesn't work in Login dialog.
Language dropdown only shows 8 lines, could show more.
Settings dialog is on top of other app windows, even when task switching. It shouldn't be.
Button order is opposite of Windows defaullt.
Install into Downloads folder, not into Program Files.
The client is really nice though, congratz!