i obtain warnings in the log file and the "app" is "mediating"

log.txt

i get a 68k exception in Task 0x1d442cf8 <Backgroud CLI [ram:helloworld-mui]> when i launch the executabe

The window has no title, no resizable gadget like the screenshot from MorphOS-Library and quit button don't work:

Hello World MUI

[EDIT] Is it possible to get the informations about styled characters of the gcc output in the output file please?