Looking at this link, I think that if criminal proceedings are brought it is obvious that such a case would be very complex and lengthy. The definition of words like "designer" - and who exactly could reasonably be considered to fall within that category - could be argued about for weeks, with various experts expressing different views.
I wonder what the procedure would be to pursue a criminal case. Presumably, evidence gathered from the inquiry just set up (if it gets off the ground) will be passed to the CPS for its consideration. Would the CPS have to appoint someone to help them understand the technicalities? It seems to me that it is very important that all the different types of regulations and guidelines for builders, heating, plumbing and electrical engineers and the input of the fire service would also be essential. There are so many issues that contributed to this disaster, including the fact that, although there are fire rescue ladders that reach to, I think it was said, 20 floors, the fire service's ladders only reachb to the 12th floor.
As I understand it, the current inquiry is of very limited scope and, as the judge intimated, it seems likely that many people will find this unsatisfactory.