Are these Standoffs? What else could be wrong?

[blueflame8]

Hey there, so before assembling everything in the case for my first build I assembled the motherboard, PSU, CPU cooler graphics card and ram outside. When shorting the power on the motherboard, everything worked - monitor recieved signal and all fans went on. Yet after assembling it in the case, nothing would happen - no lights/fans even for the PSU I could not hear the fan. So I tried breadboarding again just now and they all seem to work. I'm assuming maybe I alligned the standoffs wrongly? Can I just check these are pre-installed standoffs in my case:

Top section:

Bottom Section:

Whole inside of case:

Am I right in saying I just align them and use normal mounting screws to screw the motherboard in? This is what I did last time.
Also what else could be wrong if it works outside the case but nothing seems to happen inside?

There's no speaker as a front panel connector that came with my case so I can't check if there are any beeps
Thanks

 

[blueflame8]

That's correct, one thing though is that I'm missing one motherboard screw that goes into the standoff, is it safe to use another type?

 

[blueflame8]

Never mind, it works inside the case now!