Customize the design aspects of the VPC plots in xpose

Hello, I am trying to customize the design aspects of the VPC plots being made with xpose after a PsN run. This is how far I have reached: xpose.VPC (vpc.info="vpc1/vpc_results.csv", vpctab="vpc1/vpctab1", PI="NULL", by="STRT", PI.ci="area", PI.real=TRUE,type="p",main ="Visual Predictive Check\nPSY-xxxx Study",pch=16,PI.limits=c(0.05,0.95)) I need to make a few changes and I am hoping someone could help me: a) I need to change the multi-panel strip header. Instead of the numbers under STRT I wish to use "Dose: X mg" b) xlab and ylab don't work. How can I rename the x and y axis c) I need to change the units of the X and Y axis values (need to change time from hours to days). DV is log-transformed and I wish to retain the y-axis on a log scale but the values of the Y-axis should be displayed in concentration (ng/mL, instead of the current log-transformed values). Please help, Mahesh