syssetup: stranded in the last installation step if previously invoked the locale configuring dialogs

The use-case:
1. On 2nd stage setup, at "Regional Settings", push "Customize" to open either one of the local settings dialogs.
2. Close the local settings dialog(s) and continue with installation.

After the copying in the "Registering Components", the "Wine Gecko Installer" window is not visible (left somewhere behind the wizard window), so the user would probably wait for... I don't know!

Update: It has NOTHING TO DO with how the main wizard window handles the Wine Gecko Installer. From my tests, the problem persists even if the Gecko Install part is removed entirely from the syssetup code.
Update2: Things get stuck at VMWare video installation (in RunVMWInstall function, wizard.c, syssetup).