Hey aluka! Earlier this year, I purchased two of your traditional plakat females (1 marble, 1 cellophane) and had managed to breed the black marble one! The spawn is around 8-9 weeks now, and I'm quite surprised as I'm beginning to see strikingly similar colors as the bettas from your spawn. I've started a spawn log I'll be updating soon with much better pics of the babies, here's the link in case you're interested:
http://bettasource.com/forums/topic/...le-hmpk-spawn/