Hello
how could I increase or decrease the width of audio tracks? I inadvertently expand much a voice range and now do not know how to reduce.
Thanks.

Hello and welcome to the forum!
 
Can you provide a little more information about your system and your problem?  For instance, what version of Windows, 32 or 64 bit, Win 7, Win 8, Win 8.1 or Win 10?  What version of Music Creator?  Do you want to change the waveform amplitude (gain) or how long the waveform lasts?
 
Edit:  I see in another post you are using Music Creator 7.