I have made my first plug (MDF, 2K High Build Primer, 2K Lacquer) and need to know what is the best Release Agent to use with a new 2K covered plug and the Unimould System and can i use Newplast instead of filleting Wax ?.

I prefer to not use wax with PVA, just spray the PVA like it's a paint. The smaller the tip the better generally, PVA is quite thin (more like water than paint) so you want to spray thinner coats and allow it to dry completely before applying the next coat. It does run quite easily. 

I've been told that the tip size for PVA is 0.5-0.8mm so i'm off to buy one today. Do you spray semi-perm ?, if so can i use the same gun for both and what do i clean the gun with after PVA and Semi-Perm ?.