I've never tried to compile the examples myself. I had problems with two of the four example's .exes, when another EPM was open. I've just tried it again and all four start now.
We discussed to create our own GUI app at NEPMD. I thought that this approach was too complex, but at that time I had not even a compiler. Looking back, that seems to be not completely wrong. But alone the ETK functions have so many bugs, that I would start there first if I had the ETK source. For most of them, I've added workarounds and have now the skills to fix at least just a few of them, if the sources would have been released. The GUI would be another story, but must flaws are in the ETK. It would be much better to start with a supported and well-spread toolkit, e.g. Scintilla. Also Kate looks very promising. Of course that requires to change the compiler, too.