Tried my first Ha narrowband imaging - can't focus

Last night, I tried my first Ha narrowband imaging. But I was unable to focus the scope properly.

• Focus@ from SkyX didn't work. The stars that it would try (based on its ranges) were too dark with the narrowband filter. I tried some other stars - but they were apparently too bright and it didn't focus properly.
• I then tried to focus with the Bahtinov mask. But even after I did that as good as possible, the image wasn't properly focused.

Here is a typical image that I got:

Here is a zoomed-in image:

Need to figure this out tonight.

Furthermore:

• Can't get autoguiding with SkyX to work - have to use PHD for the time being
• The USB extension cord didn't work for the scope control. I'll try out what happens if I use a USB hub - that would have the good side effect of only having one cable routed into the house.