I started using Qucs a few days ago. I'm using the 0.0.7 Windows version. I'm actually working at my university on spiral inductors simulation and modeling. Qucs core solver, without the GUI is what I was looking for. Great job. Spice or other commerial solvers are much too big for my needs. 
The distribiution contains qucsconv program to convert Spice netlists to qucs netlist. How to use it? Using the command line I did get with -h switch on both windows version and the one I compiled under cygwin, I'm not getting any results. I used for test purposes *.cir files from PSPICE.
What could be the source of the problem?
PS. Who prepared the polish translation of Qucs. I found the existing sometimes weird and I would gladly help.