esp-idf eclipse tool chain missing

[LeonVrk]

I'm new to ESP32 (I've used Eclipse extensively on other hardware platforms).
I installed the Eclipse CDT and the ESP-IDF/Tools environment and things worked fine, until I tried to debug.
From then on I was unable to import example projects. The 'New' Espressif IDF Project did no more have a return button before Finish button.
Selecting the default project has the Build directory empty.
I reinstalled Eclipse, ESP-IDF and tools to no avail.
There must be some file with 'old' settings that I should delete.
I'm stuck.
Please help me out !!