Hi, I have a cob (chalk and flint) wall on an internal wall upstairs (between where cottage was extended years ago). I do not intend to dry line the wall, but retain the original character of 'warts and all!' As I had a 25Kg bag of left-over coving adhesive and another of plasterboard adhesive I have 'repaired' the surface by 2-3" and filled it back to the front face. (I know this is less than ideal and don't need reminding that conservationists would advise lime mortar, etc. The property is not listed). In the past I have used Tarmac Limelite as it is a compromise that overcomes the problem of traditional lime finishes and gypsum plasters, which do not work well against one another. The wall is not straight, and the cob background simply breaks up or deflects drilling on the flints or provides no support at all. The original skirting was fixed to wooden pegs driven into the wall, then nailed - as you'd expect. I don't doubt that this is the right way, but I don't want to do it. Given that I still have a fresh bag of Knauff plasterboard adhesive to use up, will it stick MDF skirting and gap-fill any irregularities at the same time? I've asked Knauff Technical and they said they don't know. They advised trialling a sample. Has anyone any experience-based comments, please? Thanks.