I read that as well in the registered user forum. And it indeed can be a possibility.

Youi definitely should try a very simple thing as a test first - to see wether it works. Best without any textures too, to come closer to the problem.

I as well on my old G4 had cases where it took more than ten minutes until anything happened. Even the Activity Monitor was saying that the program was not responding. Suddenly... So be patient, start an import anf have a dinner in between to see what happens after half an hour or so.
And if that imports, report the long time to technical support please. So that they can speed that up maybe.

One day your ship comes in - but you're at the airport.