^
try Unicode Innosetup ;-)
Some observations (Kaktor will pobably gives you proper answers)
1) the basic design looks fugly
https://imgur.com/a/X9Lif
... you might wanna create some fine looking "blank" one or tr to mess with the code a bit more
2) While installing it gets some "proc errors"
https://i.imgur.com/yc2l1Oi.png but it installs when you click ok and on finish page gets same "proc error"
3) some weird stuff happening when you click install
https://imgur.com/a/11HFb
uninstall works flawlessly