offset / loft problem

 From:  Lemo (LEMONNADO)
1181.1 
I draw a very irregular 2D curve, then I use offset to make it smaller and move that up in Z, I repeat that a couple of times. Then I try to select the curves to form a loft. The problem then is that either nothing happens, or garbage fills the screen. It seems that the offset function is breaking into little curve segments which I cannot seem to 'heal' into single curves using bool or join operations. Ideas?
Lemo