Never never never use PVA as a base for paint on new plaster..and ive never heard of mixing it with the first coat either
Living up to my 'decorating maverick' name....
Heres one that has always worked for me...
I have come across quite a few unpainted Artexed, nicotine stained lids over the years..impossible to wash down withought wrecking the Artex..
You can use specialist paints like Clissidur etc..but they are costly and stick to high heaven
Theres an easier way...either brush or use a garden spray a coating of thinned out bleach over them and allow to dry for a day, the bleach will help knock the guts out of the stain...then mix PVA with the first coat of
paint, (thinned slightly by about 15% to soak into the Artex) allow to dry thoroughly and then apply the second coat..if your using silk then you can add some more PVA to it..if your going for a matt finish then you cant do it as the PVA could leave a sheen
It always works for me and a few others I know of..
I dont read take a break for nothing you know!!