Several papers and a website by Peters (see below) address several problems ignored by this manuscript/paper including:

1. Basal pterosaur ichnites (they are known, have been published and non are quadrupedal, some are digitigade)
2. The origin of pterosaurs (among bipedal fenestrasaurs each with uropatagia, trailing each hind limb. Objections to this scenario by Hone and Benton (2007, 2008) were due to typos in their dataset and deletion of two fenestrasaurs and 75% of the data from a third along with deletion of all data from Peters 2000, an original candidate facing the alternate scenario, among many other problems).
3. The presence or absence of compressed metatarsals on pterosaurs, (typical keys to digitgrady and plantigrady).
4. The uropatagium problem. (So far observed only in one specimen, Sordes, which was shown to be an illusion caused by bone and membrane dislocation during taphonomy. All other pterosaurs and their predecessors have twin uropatagia).

Peters, D. 1995. Wing shape in pterosaurs. Nature 374, 315-316. Peters, D. 2000a. Description and Interpretation of Interphalangeal Lines in Tetrapods. Ichnos, 7: 11-41 Peters, D. 2000b. A redescription of four prolacertiform genera and implications for pterosaur phylogenesis. Rivista Italiana di Paleontologia e Stratigrafia 106: 293-336. Peters, D. 2002. A New Model for the Evolution of the Pterosaur Wing - with a twist. Historical Biology 15: 277-301. Peters, D. 2007. The origin and radiation of the Pterosauria. Flugsaurier. The Wellnhofer Pterosaur Meeting, Munich 27. Peters, D. 2009. A Reinterpretation of Pteroid Articulation in Pterosaurs - Short Communication. Journal of Vertebrate Paleontology 29(4):1327–1330, December 2009 Peters, D. 2010. In defence of parallel interphalangeal lines. Historical Biology iFirst article, 2010, 1–6 DOI: 10.1080/08912961003663500 Peters, D. 2011. A Catalog of Pterosaur Pedes for Trackmaker Identification. Ichnos 18(2):114-141. Peters, D. 2010-2015. www.reptileevolution.com https://pterosaurheresies.wordpress.com/2015/03/10/the-evolution-of-the-sordes-wing-and-uropatagia-1971-to-2011/

Hone DWE and Benton MJ 2007. An evaluation of the phylogenetic relationships of the pterosaurs to the archosauromorph reptiles. Journal of Systematic Palaeontology 5:465–469. Hone DWE and Benton MJ 2008. Contrasting supertree and total evidence methods: the origin of the pterosaurs. Zitteliana B28:35–60.