premiere rush need help

iam facing this default for more than a month with this app , it freezes my computer for days .

it studdenly shots down when iam editing or stops working inreturn i lose all the editing work. it takes for a video of 10 min to upload or render 3 hours . it wasnt like that when i started working with this app . 

help me please otherwise i need to cancel this app buy another one from another company my work timeline gets effected by this app .