Help with warning messages after take-off

I'm kind of new here so please bare with me,

After I take off, I get the indication to throttle down to the CLMB detent. But every now and then when I do this, I get a bloue and yellow message popping up on the warning display regarding the weights and asked whether to confirm. I click yes and clear and the message dissapears but leaves a blue message behind saying "LDG PERF AFFECTED" which remains there for the remainder of the flight.

Then at that moment on the left system dispay screen, I get a yellow warning saying something about BTV which I also clear. 

Also, I've noticed that the auto step climbs don't always work and are sometimes either ignored or have a message saying "ABOVE MAX FL" next to them. 

Like I say, this doesn't happen all of the time and happens on both the A359 and A35K. I've made sure both my Simbrief flight plan and the aircraft I'm curre tly flying are using the same measure units.

So are these known bugs or is it likely thatI  am doing something wrong during my pre-flight setup? 

Thanks in advance.