rncbc.org a.k.a. Rui Nuno Capela

Hm ... i rebuilt qtractor ... liblo and liblo-dev is installed.
./configure said: OSC service support (liblo) . . . . . . . . . . .: yes

But still, the button to open the GUI is missing.

Even the debug output of qtractor seems ok. it says
Testing VST compatibility...
dssi-vst-server[1]: VST 2.4 entrypoint "VSTPluginMain" not found in DLL "B4.dll", looking for "main"
dssi-vst-server[1]: VST entrypoint "main" found
dssi-vst-server[1]: plugin instantiated
dssi-vst-server[1]: plugin is a VST
dssi-vst-server[1]: plugin has a GUI

dssi-vst-server[1]: plugin supports processReplacing
dssi-vst-server[1]: opening plugin
dssi-vst-server[1]: plugin is VST 2.0 or newer
dssi-vst-server[1]: plugin is a synth
dssi-vst-server[1]: plugin name is "Native Instruments B4"
dssi-vst-server[1]: vendor string is "Native Instruments"
Initialising Windows subsystem...
dssi-vst-server[1]: registered Windows application class "dssi_vst"
dssi-vst-server[1]: created main window
done
dssi-vst-server[1]: created audio thread
DSSIVSTPluginInstance(0x1a85ec0): setting OK true
DSSIVSTPluginInstance::DSSIVSTPluginInstance(B4.dll) construction complete

Any hints ? Still if I use ./vsthost B4.dll the GUI is coming up...