Seems that qtcreator try anyway to connect a shell to the remote device when you go in run configuration and this basically block completely the UI. This is really serious because make the entire qtcreator stuck and ask to wait or crash

SOFT ASSERT [10:07:35.597]: "isSetup" in /home/qt/work/build/qt-creator/src/plugins/remotelinux/linuxdevice.cpp:1130
SOFT ASSERT [10:07:55.616]: "state() == QProcess::Running" in /home/qt/work/build/qt-creator/src/libs/utils/process.cpp:1587
qtc.remotelinux.device: Failed to start shell for: "root@192.168.0.40:20" ,  "Failed to install shell script: Timeout while trying to check for cat.\n"

I think that this happen in constructor where the panel try to get the enviroment from the remote. This "must" be done in background