Hello! I am having the same problem, when it goes to the "PlayOnMac Wizard" installation it is blank.
My version of POM is 4.3.4
MacOX Mojave
Link to image https://ibb.co/kQhZtYv
I had to apply a change in the preogram to let me run it ...
I found the change in this same forum ..
"Try to open the following file with a text editor:
/Applications/PlayOnMac.app/Contents/MacOS/playonmac
Line 25:
Replace
CurrentLocale = "$ (defaults read -g AppleLocale)"
With
CurrentLocale = "$ (defaults read com.apple.dock loc)" "
I hope you can help me! thanks!