seeker render or not

[smuglilal]

I have just finished concreteing a cellar floor now for the walls i have two earth retaining walls i would like to know which would be best a seeker render or putting the bubble stuff up and plasterboard had a little exp in both and if i plasterboard will damp come up through the concrete onto the plasterboard the concrete does have a membrane under it there is also a little coal residue left on the wall which i cant shift is this ok to go over