Blocks are confused on loading a working QCAD dxf(2000) when the first 5 characters of names are equal without space; LibreCAD generated dxf(2000) files working.
The attached dxf are corrupt.
Edit blocktest.dxf and add the follow text starting at line #1517 to solve the point #6:
Adding a patch to prevent this "corruption" is very intrusive, and not be added until is removed the "feature freeze" state.
May be open a bug report in QCad...