I have two questions regarding writing of survey papers
Firstly, if one of the technical papers reviewed has a number of figures. Take for example: Figure 4 is "Data model" and Figure 8 is "Mechanism structure". In the survey paper is it enough modification (for a waver of official permission) to merge these two into one figure and cite. Say, Figure X: Data model and Mechanism Structure adapted from [ref]?
Secondly, in the case when author A proposes "Data model" and "mechanism structure" in paper  and  i.e four entirely different diagrams. Is it sufficient as modification (for a waver for official permission) if in a survey, all four combined in one figure.
Thanks in advance