phamarus, for getting fluids or any other geo sequence into LW, just do what I do.
The latest incarnation of Realflow´s plugin for LW works nicely, so just use that to load the Houdini sequence.
Of course Houdini exports .obj and you need an .lwo sequence. Load your obj sequence with the standard LW object sequencer, and then use this script “IL_SaveTSeq” (it´s free, at
http://www.interialabs.de/lw/lscript/index.html) [interialabs.de] to convert the whole thing to a lwo sequence.
Now you use the new (LW 9.5 required) Realflow mesh sequencer and you can even texture with nodes and/or use FPrime.