When using “Filter curve EQ”, the end of a track creates a click. “Repair” doesn’t fix the problem. Please give me an info on how to fix it, I can’t continue my audio track 
Or should I downgrade back to V2.0.3?
When you apply any filter to a waveform, ensure that the start and end of the selection occur within silence:
Edit: Just checked, V2.3.3 does have this problem as well. My mistake.
Answer: I have to mix two audios together and apply filter curve to match the spectrums. How would I do it differently?
I can fix the issue by using “Vocal reduction and isolation” on separate dual mono left and right channels.
As in my previous post. If the audio selection starts and ends in a silent (or near silent) region, there won’t be a click.
I mix two audios together and sometimes splits happen in middle of the track. Can you please fix it, I’ll have to use a different program to do it, because I have no other choice.
What sort of “splits”?
I don’t understand what you mean.
You have two similar audio tracks, but one is broken. So you use the better one to fix the broken one.