i have made the same experience: none of my VFT flowers produced any
seeds, maybe this year. Growing of the seeds: put them in the usual CP
substrate, warm (20-25, maybe 30 deg. Celsius, don't know how many Fs),
keep humidity high (maybe with a foil or glass over the pot) and wait
several weeks, takes some time. I heard it is easyer and quicker to get
new plats out of the leaves of an VFT.
Ciao, Daniel.