Thanks. I'll start a separate thread for other queries - I thought that would be more inconvenient to others, though convenient to me

I am reading more theory before trying again, thats one of the reasons I took a break. It is possible that the rim is bent, but in that case I probably will not buy a new one - this bike is more for experimentation and I doubt I'll spend much more money on it. W.r.t rounding off the spoke - it is possible that I cranked down too hard, but it didn't feel like it.

Is there any way to tell if the rim is bent (at home) without unlacing the hub and laying the rim flat on a table? Again, I'm happy if its a reasonable test - I'm not flush at the moment, so buying new tools is out for now. Also, I may never become any good at wrenching - this bike is a kind of testing ground - if I enjoy it and don't suck at it too much, I will start investing in better tools.