I have a Gerber file generated with CADSTAR, I opened it with Gerbview and it looks fine but when I convert it to Pcbnew the pads turned out as holes !!? (see images below)
The problem with pad conversion is that in most old gerber files there’s no way to find footprints. If the board file is meant to be modified, it would be meaningless to leave free floating pads there. The only way forward for the user is to create footprints and put them in their places and take away the old pads, whether they are SMD pads or holes. Therefore it doesn’t matter if the old pads are just holes.
The board is too big it would be pain in the ass to make the foorprints all over again … I only need to modify some THT holes drill sizes…
I will check the thread you sent any see if anything might be useful!
That article is not going to help you much. In that FAQ article I simply deleted all footprints and replaced them with footprints from KiCad’s libraries.
I am surprised that all SMT pads are converted to via’s. Doing so for the holes in THT pads is “normal”, because the concept of “pads” does not exist in many Gerber files, and therefore Gerbview can not do much more then convert them to via’s.
Creating a KiCad project from Gerber files is far from ideal, and an excessive amount of work if your intentions are only to change some small things. The ideal tool for that would be a Gerber Editor (Instead of a Viewer). This old Eevblog thread has some links to gerber editors: https://www.eevblog.com/forum/eda/gerber-editor/
Editing your drill files with a text editor as eelik suggested may be a valid option. Depending on what you want to do, it may be as simple as changing a single number for the diameter of a specific drill.
If you still habe the design files you could try the CADSTAR importer in v5.99 (the experimental version that could potentially have bug and nasty surprises) I have hear good things about it.