Please see this as an “FYI thread” just passing on some good tips I found on the internet …
As it is I have been in need to convert Gerbers generated in a PCB layout program for g-code that I could import e.g. into Estlcam. Yesterday I found out that Flatcam can be used for that and also found good advice on how to do the conversion in practice in these videos (the most straightforward IMO are the two top ones):
One additional comment referring to the first video: When exporting the g-code files from Flatcam (last step) save the files with the extension .nc instead of .txt. If the files are saved with the .txt extension estlcam will not recognize them.