@StevenFS When you have paid for a license the Qt support line is definitely a target for your questions, since you have paid. @aha_1980 referred to the Qt bug tracker on JIRA Sometimes it worth to check there if there is already a report. Also you may others when you are posting a proper description there. Someone in charge will rate it and comment on it. Certainly nothjing to do all the time, but it is the only place where possible bugs and suggestions are tracked and monitored. Over here nobody is monitoring the issues and ensuring a solution. When you post the report number over here, others can vote for the report and raising its importance.

@nitish_linked As @SGaist said use absolute path to your qmake. If you just call qmake the system looks in some predefined locations (like /usr/bin) and in directories PATH is showing to and finds qmake from your distribution.

Some workaround for history You can install offline version then run maintance tool and add repo there(rep link looks like this http://download.qt.io/online/qtsdkrepository/windows_x86/android/qt5_55/)