Yoma 38a - Alexandria shel Mitzrayim

Here and in Arachim 10b are several incidents involving the people of Alexandria shel Mitzrayim. In each one, our Sages sought to use their skills to duplicate one of the miraculous things in the Beis Hamikdash - the lechem hapanim, the ketores, (and in Arachim) the copper bell, the copper spice-grinder. In each case, they did a good job, but something essential was missing and their work had to be abandoned. I'm not sure why, but perhaps they had a connection to Greek science?
Anyhow, I'm wondering if this is also the reason that Nikanor's famous doors were in danger of sinking into the sea in a storm - did he do anything wrong in making them? But they were also made in Alexandria shel Mitzrayim.